Ex Parte PearsonDownload PDFBoard of Patent Appeals and InterferencesSep 17, 200910241893 (B.P.A.I. Sep. 17, 2009) Copy Citation UNITED STATES PATENT AND TRADEMARK OFFICE ____________ BEFORE THE BOARD OF PATENT APPEALS AND INTERFERENCES ____________ Ex parte SIANI LYNNE PEARSON ____________ Appeal 2009-000741 Application 10/241,8931 Technology Center 2400 ____________ Decided: September 18, 2009 ____________ Before HOWARD B. BLANKENSHIP, JEAN R. HOMERE, and THU A. DANG, Administrative Patent Judges. HOMERE, Administrative Patent Judge. DECISION ON APPEAL 1 Filed on September 12, 2002. This application claims foreign priority to 0122048.2, filed on September 13, 2001. The real party in interest is Hewlett-Packard Development Company L.P. Appeal 2009-000741 Application 10/241,893 2 I. STATEMENT OF THE CASE Appellant appeals under 35 U.S.C. § 134(a) from the Examiner’s final rejection of claims 1 through 20. Claims 21 through 35 have been withdrawn. We have jurisdiction under 35 U.S.C. § 6(b). We affirm. Brief Summary of the Invention Appellant invented a method and apparatus for obtaining a profile of a user across a network computer system. (Spec. 1, ll. 8-10.) Appellant’s Figure 1 depicts a user apparatus (10) that includes a capture unit (12) for capturing profile characteristics. (Spec. 17, ll. 6-7.) The user apparatus (10) further includes a profile unit (13) for forming a user self-profile based upon a user identity as established by the trusted platform (11) and one or more profile characteristics captured by the capture unit (12). (Spec. 18, ll. 1-5.) Each user self-profile is stored and maintained on the user apparatus (10). (Spec. 18, ll. 11-12.) According to Appellant, after the user apparatus (10) creates a user self-profile, it makes the user self-profile available to each inquiry apparatus (20). (Spec. 13, ll. 18-20.) Illustrative Claim Independent claim 1 further illustrates the invention as follows: 1. A method for obtaining a user profile of a user for storage on a user accessible computing apparatus and for sharing the profile, comprising the steps of: capturing at least one profile characteristic associated with said user; combining identity information of said user and the captured profile characteristic to form a user self-profile; storing said user self-profile on said user accessible computing apparatus; and Appeal 2009-000741 Application 10/241,893 3 making the user self-profile available to one or more remote computers together with information verifying a trusted status of said user accessible computing apparatus in response to an inquiry received therefrom. Prior Art Relied Upon The Examiner relies on the following prior art as evidence of unpatentability: Docter US 6,330,610 B1 Dec. 11, 2001 (filed Dec. 4, 1997) Guheen US 6,519,571 B1 Feb. 11, 2003 (filed May 27, 1999) Miettinen WO 01/54346 A1 July 26, 2001 Rejections on Appeal The Examiner rejects the claims on appeal as follows: Claims 1, 2, 6 through 9, and 12 through 17 stand rejected under 35 U.S.C. § 103(a) as being unpatentable over the combination of Guheen and Docter. Claims 5 and 20 stand rejected under 35 U.S.C. § 103(a) as being unpatentable over the combination of Guheen and Miettinen. Claims 3, 4, 10, 11, 18, and 19 stand rejected under 35 U.S.C. § 103(a) as being unpatentable over the combination of Guheen, Docter, and Miettinen. Appellant’s Contentions 1. Appellant contends that the Examiner erred in concluding that the combination of Guheen and Docter renders independent claim 1 unpatentable. In particular, Appellant argues: Appeal 2009-000741 Application 10/241,893 4 (a) Guheen’s disclosure of a global directory for storing user profiles, in conjunction with employing authentication protocols, does not teach making available information verifying a trusted status of said user accessible computing apparatus. (App. Br. 5-6; Reply Br. 2-3.) (b) Guheen’s disclosure of developing a user profile, in conjunction with creating a user profile from information about a user, does not teach capturing a least one profile characteristic associated with said user and combining identity information of said user and the captured profile characteristic to form a user self-profile. (App. Br. 6-12; Reply Br. 3-6.) 2. Appellant contends that the Examiner erred in concluding that the combination of Guheen and Docter renders independent claim 16 unpatentable. In particular, Appellant argues: (a) There is insufficient rationale for the proffered combination. (App. Br. 13-14; Reply Br. 8.) (b) Guheen’s disclosure of storing a user profile in a global directory where it can be accessed by users from anywhere in the network teaches away from Docter’s disclosure of storing the user self-profile on a client computer. (App. Br. 14-15.) 3. Appellant contends that the Examiner erred in concluding that the combination of Guheen and Miettinen renders independent claims 5 and 20 unpatentable. In particular, Appellant argues: (a) Miettinen is non-analogous art because it is not in the field of Appellant’s endeavor. (App. Br. 16-17.) (b) There is insufficient rationale for the proffered combination. (App. Br. 17-18; Reply Br. 8-9.) Appeal 2009-000741 Application 10/241,893 5 Examiner’s Findings and Conclusions 1. The Examiner concludes that the combination of Guheen and Docter renders independent claim 1 unpatentable. In particular, the Examiner finds that: (a) Guheen’s disclosure of a global directory for storing user profiles, in conjunction with employing authentication protocols that verify users requesting to access an inquiry resource, teaches making the user self- profile available to one or more remote computers together with information verifying a trusted status of said user accessible computing apparatus. (Ans. 19-21.) (b) Guheen’s disclosure of developing a profile from many sources by capturing information from a user as he or she uses the network, in conjunction with associating particular data stored on the server with a particular user, teaches capturing a least one profile characteristic associated with said user and combining identity information of said user and the capture profile characteristic to form a user self-profile. (Ans. 21-23.) 2. The Examiner concludes that the combination of Guheen and Docter renders independent claim 16 unpatentable. In particular, the Examiner finds that: (a) Guheen’s disclosure of a user identification system and, in particular, utilizing a user profile to customize an interface, in conjunction with Docter’s disclosure of filtering data in multiple stages without exposing private information to un-trusted servers, teaches the claimed invention. (Ans. 25-27.) Appeal 2009-000741 Application 10/241,893 6 (b) Guheen’s disclosure of storing a user profile on a global directory can be modified to function in a similar manner to Docter’s disclosure of storing profile data on a client server. (Ans. 27-29.) 3. The Examiner concludes that the combination of Guheen and Miettinen renders independent claims 5 and 20 unpatentable. In particular, the Examiner finds that: (a) Miettinen’s disclosure of obtaining an electronic identity from its own previous user profile that was captured and stored on a server is analogous to Guheen’s disclosure of storing a user profile on a global directory. (Ans. 29-30.) (b) Miettinen’s disclosure of obtaining an electronic identity from its own previous user profile that was captured and stored on a server, in conjunction with Guheen’s disclosure of developing a profile from many sources by capturing information from a user as he or she uses the network, teaches the claimed invention. (Ans. 30-31.) II. ISSUES 1. Has Appellant shown that the Examiner erred in concluding that the combination of Guheen and Docter renders independent claim 1 unpatentable? In particular, the issue turns on whether: (a) Guheen teaches making the user self-profile available to one or more remote computers together with information verifying a trusted status of said user accessible computing apparatus in response to an inquiry received therefrom, as recited in independent claim 1. (b) Guheen teaches capturing a least one profile characteristic associated with said user and combining identity information of said user Appeal 2009-000741 Application 10/241,893 7 and the capture profile characteristic to form a user self-profile, as recited in independent claim 1. 2. Has Appellant shown that the Examiner erred in concluding that the combination of Guheen and Docter renders independent claim 16 unpatentable? In particular, the issue turns on whether: (a) There is sufficient rationale for the proffered combination. (b) Guheen’s disclosure of storing a user profile in a global directory where it can be accessed by users from anywhere in the network teaches away from Docter’s disclosure of storing a user self-profile on a client computer. 3. Has Appellant shown that the Examiner erred in concluding that the combination of Guheen and Miettinen renders independent claims 5 and 20 unpatentable? In particular, the issue turns on whether: (a) Miettinen is within the scope of the prior art analogous to the claimed invention. (b) There is sufficient rationale for the proffered combination. III. FINDINGS OF FACT The following Findings of Fact (“FFâ€) are shown by a preponderance of the evidence. Appellant’s Invention 1. Appellant’s invention generally relates to maintaining privacy while releasing relevant profile characteristics of interest to inquirers. (Spec. 5, ll. 22-25.) Appeal 2009-000741 Application 10/241,893 8 Guheen 2. Guheen generally relates to user identification systems and processes and, in particular, pertains to utilizing a user profile to customize an interface. (Col. 1, ll. 6-8.) Guheen discloses a multi-protocol, scalable global directory for storing information such as user definitions, user profiles, network resource definitions, and configuration parameters. (Col. 15, ll. 65-67.) It employs naming, directory, and authentication protocols on top of a shared, distributed, object repository. (Col. 15, ll. 67-68.) Users and applications can use the directory to locate and access information from anywhere in the network. (Col. 15, ll. 68-69.) 3. Guheen’s Figure 68 depicts developing a customer’s profile (1610). (Col. 180, ll. 18-19.) This profile may be developed from many sources including customer input, customer buying habits, customer income level, customer search habits, customer profession, customer education level, customer’s purpose of the pending sale, customer’s shopping habits, etc. (Col. 180, ll. 19-23.) Such information may be input directly by the user, captured as a user uses the network, and maybe downloaded periodically from a user’s system. (Col. 180, ll. 24-26.) 4. Guheen discloses a typical database or filed-based shopping cart system that requires the user to be uniquely identified in order to associate particular data stored on the server with a particular user. (Col. 182, ll. 40-43.) This requires the user to log-in or create an account, which is then stored on the server. (Col. 182, ll. 43-45.) 5. Guheen discloses maintaining a security log and user profile of what was accessed when, from a computer resource, facility and data view point. (Col. 148, ll. 29-31.) Appeal 2009-000741 Application 10/241,893 9 Docter 6. Docter generally relates to a data filtering system that filters data in multiple stages. (Abstract.) In particular, the first filter criteria and the second filter criteria can be included in a profile data set. (Abstract.) The profile data set may be associated with a particular data recipient. (Abstract.) Further, Docter’s Figure 2 depicts a flow diagram that illustrates a procedure for performing multi-stage data filtering. (Col. 4, ll. 48-49.) At step (40), a profile data set is generated and stored on a client. (Col. 4, ll. 51-53.) 7. Docter’s Figure 3 depicts that the server requests filter criteria from the client at step (64). (Col. 5, ll. 39-41.) In response to the server’s request for filter criteria, the client determines the level of trust associated with the requesting server at step (66). (Col. 5, ll. 41-43.) At step (68), the client transmits profile data elements associated with the server’s level of trust to the server. (Col. 5, ll. 43-45.) Miettinen 8. Miettinen generally relates to secure communication whereby entities are often required to electronically authenticate themselves before utilizing services or executing a transaction. (Pg. 1, ll. 16-19.) In particular, Miettinen discloses issuing an electronic identity based on a previously certified electronic identity and, in particular, using a previously certified identity to create another representational form for the same identity. (Abstract.) Further, Miettinen discloses that the previously certified identity can be called a mobile identity, which is associated with a person’s mobile terminal or mobile phone. (Abstract.) Miettinen discloses linking a mobile phone owner’s (presumably anonymous) network identification number Appeal 2009-000741 Application 10/241,893 10 (“NIDâ€) with a public pretty good privacy (“PGPâ€) identity via an encrypted channel. (Pg. 14, ll. 20-22.) IV. PRINCIPLES OF LAW Obviousness “On appeal to the Board, an applicant can overcome a rejection [under § 103] by showing insufficient evidence of prima facie obviousness or by rebutting the prima facie case with evidence of secondary indicia of nonobviousness.†In re Rouffet, 149 F.3d 1350, 1355 (Fed. Cir. 1998). Section 103 forbids issuance of a patent when “the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains.†KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 406 (2007). In KSR, the Supreme Court emphasized “the need for caution in granting a patent based on the combination of elements found in the prior art,†and discussed circumstances in which a patent might be determined to be obvious. Id. at 415 (citing Graham v. John Deere Co., 383 U.S. 1, 13-14 (1966)) (citation omitted). The Court reaffirmed principles based on its precedent that “[t]he combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results.†Id. at 416. The operative question in this “functional approach†is thus “whether the improvement is more than the predictable use of prior art elements according to their established functions.†Id. at 415, 417. Appeal 2009-000741 Application 10/241,893 11 In identifying a reason that would have prompted a person of ordinary skill in the relevant field to combine the prior art teachings, the Examiner must show some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness. KSR, 550 U.S. at 418 (quoting In re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006)). Teaching Away “What the prior art teaches and whether it teaches toward or away from the claimed invention . . . is a determination of fact.†Para-Ordnance Mfg., Inc. v. SGS Importers Int'l, Inc., 73 F.3d 1085, 1088 (Fed. Cir. 1995) (citations omitted). “A reference may be said to teach away when a person of ordinary skill, upon reading the reference, would be discouraged from following the path set out in the reference, or would be led in a direction divergent from the path that was taken by the applicant.†In re Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994). Teaching an alternative or equivalent method, however, does not teach away from the use of a claimed method. In re Dunn, 349 F.2d 433, 438 (CCPA 1965). Analogous Art “Whether a reference in the prior art is ‘analogous’ is a fact question.†In re Clay, 966 F.2d 656, 658 (Fed. Cir. 1992) (citing Panduit Corp. v. Dennison Mfg. Co., 810 F.2d 1561, 1568 n.9 (Fed. Cir. 1987)). Two criteria have evolved for answering the question: “(1) whether the art is from the same field of endeavor, regardless of the problem addressed, and (2) if the reference is not within the field of the inventor’s endeavor, whether the reference still is reasonably pertinent to the particular problem with which the inventor is involved.†Id. at 658-59 (citing In re Deminski, 796 F.2d 436, 442 (Fed. Cir. 1986); In re Wood, 599 F.2d 1032, 1036 (CCPA 1979)). Appeal 2009-000741 Application 10/241,893 12 V. ANALYSIS Claim 1 Independent claim 1 recites, in relevant parts: 1) making the user self-profile available to one or more remote computers together with information verifying a trusted status of said user accessible computing apparatus in response to an inquiry received therefrom; 2) capturing a least one profile characteristic associated with said user; and 3) combining identity information of said user and the captured profile characteristic to form a user self-profile. As detailed in the Findings of Fact section above, Guheen discloses a scalable global directory for storing user profiles. (FF 2.) In particular, Guheen discloses that users and applications can use the directory to locate and access information from anywhere in the network. (Id.) We find that by allowing potential users to access various user profiles in the global directory from anywhere in the network, Guheen teaches making the user profiles available to one or more remote computers, as recited in independent claim 1. Further, Guheen discloses that the multi-protocol global directory employs authentication protocols. (Id.) We find that Guheen’s disclosure teaches a global directory that employs authentication protocols to verify the status of a user requesting access thereby making available information verifying a trusted status of the user accessible computing apparatus in response to an inquiry received therefrom, as recited in independent claim 1. We are not persuaded by Appellant’s argument that Guheen’s disclosure of authentication protocols does not teach an integrity metric that is formed by a trusted platform module and further represents the status and condition of a user apparatus. (Reply Br. 3.) Appellant’s argument is not commensurate in Appeal 2009-000741 Application 10/241,893 13 scope with the claim language since it does not recite any such integrity metric representing the condition of the user apparatus. Further, Guheen discloses developing a customer’s profile utilizing many sources including, but not limited to, customer input and customer buying habits. (FF 3.) In particular, Guheen discloses that the customer profile information may be directly inputted by a user or captured as a user uses the network. (Id.) We find that Guheen’s disclosure teaches developing a customer or user profile by capturing information as the user uses the network. We thus agree with the Examiner that Guheen’s disclosure of developing a customer or user profile by capturing information as the user uses the network teaches capturing a least one profile characteristic associated with said user, as recited in independent claim 1. Additionally, Guheen discloses that a user must be uniquely identified in order to associate particular data stored on the server with a particular user. (FF 4.) This requires that the user log-in or create an account, which is then stored on the server. (Id.) Further, Guheen discloses maintaining a security log and user profile of the information accessed by the user. (FF 5.) We find that Guheen’s disclosure teaches associating a user with a user profile by requiring the user to log-in to the system. Further, as discussed above, we find that Guheen’s disclosure teaches developing a customer or user profile by capturing information as the user uses the network. In summary, we find that Guheen’s disclosure of associating a user with a user profile by requiring the user to log-in to the system, in conjunction with developing a customer or user profile by capturing information as the user uses the network, teaches combining identity information of said user and Appeal 2009-000741 Application 10/241,893 14 the captured profile characteristic to form a user self-profile, as recited in independent claim 1. We are not persuaded by Appellant’s argument that the Examiner pieces together different embodiments of Guheen without any consideration as to what Guheen actually teaches. (App. Br. 7; Reply Br. 5-6.) In KSR, the Supreme Court emphasized that “in many cases a person of ordinary skill will be able to fit the teachings of multiple patents together like pieces of a puzzle.†KSR, 550 U.S. at 420. Therefore, as discussed above, it is our view that an ordinarily skilled artisan would have been able to fit the teachings of Guheen together like pieces of a puzzle. Further, Appellant argues that “the final rejection does not include, either explicitly or implicitly in view of the prior art applied, an indication of the level of ordinary skill in the art.†(Reply Br. 7.) However, the absence of an explicit finding concerning the level of ordinary skill in the art is not reversible error if the prior art references relied on by the Examiner reflect a sufficient level of skill to support the rejection. See Okajima v. Bourdeau, 261 F.3d 1350, 1355 (Fed. Cir. 2001). As detailed in the Findings of Fact section above, the level of skill in the art is reflected in Guheen and Docter’s disclosure of storing and sharing user profile information, including associated identification information and captured profiles characteristics. Therefore, a lack of a specific finding that an ordinarily skilled artisan is one familiar with storing and sharing user-profiles on a computer is not reversible error. It follows that Appellant has not shown that the Examiner erred in concluding that the combination of Guheen and Docter renders independent claim 1 unpatentable. Appeal 2009-000741 Application 10/241,893 15 Claims 2, 6 though 9, and 12 through 15 Appellant does not provide separate arguments with respect to claims 2, 6 through 9, and 12 through 15. Therefore, we select claim 1 as being representative of the cited claims. Consequently, Appellant has not shown error in the Examiner’s rejection of claims 2, 6 through 9, and 12 through 15 for the reasons set forth in our discussion of claim 1 above. 37 C.F.R. § 41.37(c)(1)(vii). Claim 16 As set forth above, we find that Guheen’s disclosure teaches a global directory that allows potential users to access various user profiles from anywhere in the network, employs authentication protocols to verify the status of a user requesting access, and develops a customer or user profile by capturing information as the user uses the network. Further, Docter’s disclosure complements Guheen by storing a profile data set associated with a particular data recipient on a client computer. (FF 6.) Thus, we find that Guheen and Docter disclose prior art elements that perform their ordinary functions to predictably result in a method and apparatus for making a user self-profile available to an inquiry apparatus by obtaining a profile of a user utilizing a user identity and respective captured profile characteristics. See KSR, U.S. at 418-419. Further, Appellant argues that Guheen’s disclosure of storing a user profile in a global directory where it can be accessed by users from anywhere in the network teaches away from Docter’s disclosure of storing a user self-profile on a client computer. (App. Br. 14-15.) We do not agree. As set forth above, we find that Docter discloses storing a profile data set associated with a particular data recipient on a client computer. (Id.) In Appeal 2009-000741 Application 10/241,893 16 particular, we find that Docter discloses that the client computer transmits profile data elements to a server based on the server’s access request. (FF 7.) Appellant has shown nothing in Docter that would have discouraged an ordinarily skilled artisan from preventing access to a user profile stored on a client computer. Appellant has not pointed to an explicit disclosure within Docter stating that user profiles cannot be stored on a client computer and accessed via a server. Instead, Docter’s disclosure of transmitting profile data elements stored on a client computer to a server based on the server’s access request is an alternative or equivalent teaching to storing a user profile on a global directory where it can be accessed by users from anywhere in the network. (Ans. 28-29.) Therefore, Appellant has not shown that Docter’s disclosure of transmitting profile data elements stored on a client computer to a server based on a server’s access request teaches away from Guheen disclosure of storing a user profile in a global directory where it can be accessed by users from anywhere in the network. Appellant’s argument that the Examiner has not provided sufficient rationale to warrant the proffered combination is unavailing. Additionally, as discussed above, by allowing potential users to access various user profiles in the global directory from anywhere in the network, Guheen teaches making the user profiles available to one or more remote computers. In particular, we find that Guheen’s disclosure of accessing a user profile on the global directory server also teaches storing a user-profile on a user apparatus, as recited in independent claim 16. Thus, alternatively, Guheen teaches all the claim limitations of independent claim 16. It follows that Appellant has failed to show that the Examiner erred in concluding the Appeal 2009-000741 Application 10/241,893 17 combination of Guheen and Docter renders independent claim 16 unpatentable. Claim 17 Appellant does not provide separate arguments with respect to claim 17. Therefore, we select claim 16 as being representative of the cited claim. Consequently, Appellant has not shown error in the Examiner’s rejection of claim 17 for the reasons set forth in our discussion of claim 16 above. 37 C.F.R. § 41.37(c)(1)(vii). Claims 5 and 20 We find that Miettinen reasonably pertains to the problem with which Appellant was concerned at the time of the claimed invention. In particular, Appellant sought to maintain privacy by uniquely identifying users while releasing relevant profile characteristics of interest to potential enquirers. (FF 1.) Similarly, Miettinen generally relates to secure communication whereby entities are often required to electronically authenticate themselves before utilizing services or executing a transaction. (FF 8.) We find that Miettinen’s disclosure of secure communications reasonably pertains to Appellant’s solution for maintaining privacy. Therefore, Appellant’s argument is not persuasive. As set forth above, we find that Guheen’s disclosure teaches a global directory that allows potential users to access various user profiles from anywhere in the network, employs authentication protocols to verify the status of a user requesting access, and develops a customer or user profile by capturing information as the user uses the network. Further, Miettinen’s disclosure complements Guheen by issuing an anonymous electronic identity based on a previously certified electronic identity to create another Appeal 2009-000741 Application 10/241,893 18 representational form for the same identity. (Id.) Thus, we find that Guheen and Miettinen disclose prior art elements that perform their ordinary functions to predictably result in a method and apparatus for making the user self-profile available to each inquiry apparatus by obtaining a profile of a user across a network computer system utilizing an anonymous user identity and respective captured profile characteristics. See KSR, U.S. at 418-419. It follows that Appellant has not shown that the Examiner erred in concluding that the combination of Guheen and Miettinen renders independent claims 5 and 20 unpatentable. Claims 3, 4, 10, 11, 18, and 19 Appellant submits that since the combination of Guheen and Docter does not teach the claim limitations of independent claims 1 and 16, the combination of Guheen, Docter, and Miettinen does not render dependent claims 3, 4, 10, 11, 18, and 19 unpatentable. (App. Br. 19-20.) As discussed above, we have found no such deficiencies in the Guheen and Docter combination for Miettinen to cure. It follows that Appellant has not shown that the Examiner erred in concluding that the combination of Guheen, Docter, and Miettinen renders dependent 3, 4, 10, 11, 18, and 19 unpatentable. VI. CONCLUSIONS OF LAW Appellant has not shown that the Examiner erred in concluding that: 1. the combination of Guheen and Docter renders claims 1, 2, 6 through 9, and 12 through 17 unpatentable under 35 U.S.C. § 103(a). 2. the combination of Guheen and Miettinen renders claims 5 and 20 unpatentable under 35 U.S.C. § 103(a). Appeal 2009-000741 Application 10/241,893 19 3. the combination of Guheen, Docter, and Miettinen renders claims 3, 4, 10, 11, 18, and 19 unpatentable under 35 U.S.C. § 103(a). VII. DECISION We affirm the Examiner’s decision to reject claims 1 through 20 under 35 U.S.C. § 103(a). No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv). AFFIRMED erc HEWLETT-PACKARD COMPANY Intellectual Property Administration 3404 E. Harmony Road Mail Stop 35 FORT COLLINS, CO 80528 Copy with citationCopy as parenthetical citation