Ex Parte Schulz et alDownload PDFPatent Trial and Appeal BoardNov 13, 201713311951 (P.T.A.B. Nov. 13, 2017) Copy Citation United States Patent and Trademark Office UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O.Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 13/311,951 12/06/2011 Uwe Schulz KOA0335PUSA (R 1880) 1916 22045 7590 11/15/2017 RROOKS KTTSHMAN P C EXAMINER 1000 TOWN CENTER GARDNER, SHANNON M TWENTY-SECOND FLOOR SOUTHFIELD, MI 48075 ART UNIT PAPER NUMBER 1757 NOTIFICATION DATE DELIVERY MODE 11/15/2017 ELECTRONIC Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address(es): docketing @brookskushman.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte UWE SCHULZ and PAVLOS PLATANOS Appeal 2016-007496 Application 13/311,951 Technology Center 1700 Before GEORGE C. BEST, JULIA HEANEY, and SHELDON M. McGEE, Administrative Patent Judges. BEST, Administrative Patent Judge. DECISION ON APPEAL The Examiner finally rejected claims 1—3, 6—9, and 17—21 of Application 13/311,951 under 35 U.S.C. §112,11 for failing to comply with the written description requirement. Final Act. (September 4, 2015). The Examiner also rejected claim 17 under 35 U.S.C. § 102(e) as anticipated. Id. The Examiner further rejected claims 1—3, 6—9, and 18—21 under 35 U.S.C. § 103(a) as obvious. Id. Appellants1 seek reversal of these rejections pursuant to 35 U.S.C. § 134(a). We have jurisdiction under 35 U.S.C. § 6. 1 Kostal Industrie Elektrik GmbH is identified as the real party in interest. Appeal Br. 2. Appeal 2016-007496 Application 13/311,951 For the reasons set forth below, we affirm-in-part. BACKGROUND The ’951 Application describes a solar assembly having an electrical connection and junction box and a solar cell module. Spec. 1 6. The junction box design allows for more automated assembly of the components, thereby contributing to cost savings and quality improvements. Id. Claims 1 and 17 are representative of the ’951 Application’s claims and are reproduced below from the Claims Appendix of the Appeal Brief, with emphasis added to limitations that are material to our analysis: 1. A solar assembly comprising: an electrical connection and junction box having an electrically conducting structure including an electrical conductor path; a solar cell module having an electrical conductive strip; and a flexible electric conductor materially bonded with the conductor path in an electrically conducting manner and materially bonded with the conductive strip in an electrically conducting manner, without the conductive strip being bent to be materially bonded with the electric conductor, such that the conductor path electrically contacts the conductive strip via the electric conductor. Appeal Br. Claims App. 1 (emphasis added). 17. A solar assembly comprising: an electrical connection and junction box having an electrically conducting structure including an electrical conductor path; a solar cell module having an electrical conductive strip; and a flexible electric conductor materially bonded with the conductor path in an electrically conducting manner and materially bonded with the conductive strip in an electrically 2 Appeal 2016-007496 Application 13/311,951 conducting manner such that the conductor path electrically contacts the conductive strip via the electric conductor. Appeal Br. Claims App. 2 (emphasis added). REJECTIONS On appeal, the Examiner maintains2 the following rejections: 1. Claims 1—3 and 6—9 are rejected under 35 U.S.C. §112,11 for failure to comply with the written description requirement. Answer 2. 2. Claim 17 is rejected under 35 U.S.C. § 102(e) as anticipated by Rueggen.3 Answer 2. 3. Claims 1 and 8 are rejected under 35 U.S.C. § 103(a) as unpatentable over Werner.4 Answer 2. 4. Claim 9 is rejected under 35 U.S.C. § 103(a) as unpatentable over Werner as evidenced by Cohen.5 Answer 2. 5. Claims 2, 3, 6, and 7 are rejected under 35 U.S.C. § 103(a) as unpatentable over the combination of Werner and Hacke.6 Answer 3. 2 The Examiner has withdrawn the rejection of claims 17—21 for failure to comply with the written description requirement. Answer 3. 3 US 2011/0092094 Al, published April 21, 2011. 4 US 7,097,516 B2, issued August 29, 2006. 5 US 4,356,251, issued October 26, 1982. 6 US 2008/0216887 Al, published September 11, 2008. 3 Appeal 2016-007496 Application 13/311,951 6. Claims 18—21 are rejected under 35 U.S.C. § 103(a) as unpatentable over the combination of Rueggen and Hacke. Answer 3. DISCUSSION Rejection 1. The Examiner maintains the rejection of claims 1—3 and 6—9 under §112, 1 for failure to comply with the written description requirement. In particular, the Examiner found that the ’951 Application’s Specification fails to provide explicit support for claim 1 ’s limitation requiring the flexible conductor to be materially bonded to the conductive strip “without the conductive strip being bent to be materially bonded with the electric conductor.” Final Act. 3. Claims 2, 3, and 6—9 are rejected by virtue of their dependency from claim 1. Id. The claim language that the Examiner found was not supported by the written description is a negative limitation. Such limitations are adequately supported when the Specification describes a reason to exclude the relevant structure. See Santarus, Inc. v. Par Pharm., Inc., 694 F.3d 1344, 1351 (Fed. Cir. 2012). Here, Appellants argue that the ’951 Application’s Specification provides adequate support for the negative limitation. Appeal Br. 4—5 (citing Spec. 1 5, Figure 1). For the following reasons, we determine that the Examiner erred by finding that the ’951 Application’s Specification does not provide adequate support for the subject matter of claim 1. Answer 3—5. With respect to the negative limitation at issue, we agree with Appellants that Figure 1 shows “perfectly flat, non-bent conductive strips (2) materially bonded with respective electrical conductors (5).” Appeal Br. 4. 4 Appeal 2016-007496 Application 13/311,951 Paragraph 5 of the ‘951 Application’s Specification explains why Appellants use non-bent conductive strips in their invention. In particular, the Specification describes the prior art junction box as including conductive strips from the solar cell module that are bent to create contact with the connector device in the junction box. Spec. 1 5. The Specification explains that “[tjhis type of contacting requires extensive handling of the conductive strips, which handling can only be automated to a small extent.” Id. See also Reply Br. 1—3. The Examiner argues that Appellants cannot rely upon the disclosure provided by Figure 1 because the ‘951 Application’s Specification states: “The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.” Given that features of Figure 1 “may be exaggerated or minimized,” surface distortion (e.g.[,j bends/buckles/wrinkles/topographical textures) of conductive strips (2) may not be visually represented in the Figure. Therefore Appellant’s Figure 1 cannot be relied upon to establish that the conductive strips (2) are not bent. Answer 5 (quoting Spec. 114). The Examiner’s argument is not persuasive. A claim limitation complies with the written description requirement if the specification conveys with reasonable clarity to those skilled in the art that the inventor was in possession of the invention as of the application’s filing date. Carnegie Mellon Univ. v. Hoffmann-LaRoche Inc., 541 F.3d 1115, 1122 (Fed. Cir. 2008). In this case, a person having ordinary skill in the art would lookat Figure 1, would have seen a depiction of a conductive strip that is free from bends. This depiction, when combined with the Specification’s 5 Appeal 2016-007496 Application 13/311,951 explanation that the prior art’s use of a bent conductive strip precluded automation of the assembly process and a person of ordinary skill in the art’s knowledge of automated assembly’s advantages, is sufficient to demonstrate and support claim 1 ’s use of the negative claim limitation. We, therefore, reverse the rejection of claim 1 for lack of written description support. Accordingly, we also reverse the rejection of claims 2, 3, and 6—9. Rejection 2. The Examiner rejected claim 17 as anticipated by Rueggen. Final Act. 4 (citing Rueggen Figs. 1 & 2). “‘[Anticipation’” requires lack of novelty of the invention as claimed. The invention must have been known to the art in the detail of the claim; that is, all of the elements and limitations of the claim must be shown in a single prior reference, arranged as in the claim.” Karsten Mfg. Corp. v. Cleveland Golf Co., 242 F.3d 1376, 1383 (Fed. Cir. 2001). See also In re Gleave, 560 F.3d 1331, 1334 (Fed. Cir. 2009). In rejecting claim 17, the Examiner found, in relevant part that Rueggen describes [a] flexible electric conductor materially bonded with the conductor path in an electrically conducting manner and materially bonded with the conductive strip in an electrically conducting manner such that the conductor path electrically contacts the conductive strip via the electric conductor (strip 6 Appeal 2016-007496 Application 13/311,951 conductors, 4[,] contact tongues, 11 [,] of conductor rails, 8[,] for electrical connection between 4 and 6). Final Act. 4 (referencing Rueggen Figs. 1 & 2). Thus, in the Examiner’s rejection, Rueggen’s conductor rails 7 and 8 correspond to the claimed flexible electric conductor.7 Appellants argue that this rejection should be reversed because the Examiner erred by finding that Rueggen describes an assembly including “a flexible electric conductor materially bonded with the conductor path in an electrically conducting manner.” Appeal Br. 8—11. In particular, Appellants argue that Rueggen describes neither a flexible conductor nor a conductor materially bonded with the conductor path. Id.', see also Reply Br. 3. We address these arguments seriatim. First, Appellants argue that the Examiner erred in finding that Rueggen describes a flexible electric conductor that is materially bonded with the conductor path in an electrically conducting manner. Appeal Br. 9. Appellants’ argument is based upon a misunderstanding of the Examiner’s rejection. In the rejection, the combination of conductor rails 7 and 8 in Rueggen corresponds to the claimed flexible electric conductor, while wire 6 corresponds to the claimed electrical conductor path. In Rueggen, wire 6 is connected to conductor rail 8 by a solder connection through connecting element5. Rueggen 125. Thus, Rueggen describes a flexible electric conductor that is materially bonded to the conductor path. Appellants’ argument regarding the connection between conductor rail 7 and conductor 7 We recognize that the Final Action does not include reference number 7 in the statement of the rejection. The rejection, however, uses the plural “conductor rails.” Thus, we conclude that the Examiner's omission of reference 7 from the statement of the rejection was an inadvertent error. 7 Appeal 2016-007496 Application 13/311,951 rail 8 is irrelevant because the claim does not require the flexible electric conductor to have a unitary construction. Second, Appellants argue that the Examiner erred by finding that Rueggen describes a flexible electric conductor. Appeal Br. 10-11. As discussed above, the Examiner found that the combination of Rueggen’s conductor rails 7 and 8 corresponds to the claimed flexible electric conductor. Final Act. 4. Rueggen states that conductor rails 7 and 8 are fabricated from sheet metal in the form of bent punched components. Rueggen 122. Appellants argue that this fabrication means that conductor rails 7 and 8 are not flexible as that term is used in the claims of the ’951 Application. Appeal Br. 10-11. We are not persuaded by Appellants’ argument. We begin by determining the meaning of the claim term “flexible.” Oakley, Inc. v. Sunglass Hut Int 7, 316 F.3d 1331, 1339 (Fed. Cir. 2003) (explaining that anticipation and obviousness require comparison of the properly construed claims to the available prior art). During prosecution, the PTO gives the language of the proposed claims the broadest reasonable meaning of the words in their ordinary usage as they would be understood by one of ordinary skill in the art, taking into account any definitions or other enlightenment provided by the written description contained in the applicant’s specification. In re Morris, 127 F.3d 1048, 1054—55 (Fed. Cir. 1997). In this case, than ’951 Application’s Specification does not contain a definition of the term “flexible.” Thus, a person of ordinary skill in the art would have understood “flexible” to have its ordinary meaning, which is “capable of being bent or flexed.” See, e.g., Flexible - definition of flexible by The Free Dictionary, The Free Dictionary (November 7, 2017 5:11 pm), 8 Appeal 2016-007496 Application 13/311,951 https://www.thefreedictionary.com/flexible; Flexible \ Define Flexible at Dictionary.com, Dictionary.com (November 7, 2017 5:10 pm), http://www.dictionary.com/browse/flexible. Applying this claim construction, we determine that the Examiner did not err by finding that Rueggen describes a flexible electric conductor. As discussed above, Rueggen describes conductor rails 7 and 8 as being fabricated from sheet metal in the form of bent punched components. Rueggen 122. Appellants’ argument that a person of ordinary skill in the art would not understand sheet metal as being flexible as that term is used in the ’951 Application is not persuasive. In that regard, we note that the ’951 Application’s Specification itself describes parts fabricated from sheet metal as being flexible. Spec. 122 (“In the illustrated embodiment, conductor paths 3 of the conducting structure of the junction box are fabricated as flexible stamped parts from a sheet material having good electrical conductivity, for example, from hot dip tinned sheet copper.” (emphasis added)). For the reasons set forth above, we affirm the rejection of claim 17 as anticipated by Rueggen. Rejection 3. The Examiner rejected claims 1 and 8 as unpatentable over Werner. Final Act. 5— 7. Appellants argue that this rejection should be reversed because the Examiner erred by finding that Warner describes or suggests each of claim 1 ’s limitations. Appeal Br. 11—14. Appellants do not present separate arguments for reversal of the rejection with respect to claim 8, which depends from claim 1. See id. Accordingly, we select claim 1 as representative of the claims subject to this rejection and so limit our 9 Appeal 2016-007496 Application 13/311,951 discussion. 37 C.F.R. § 41.37(c)(l)(iv) (2015). Dependent claim 8 will stand or fall with claim 1. Appellants argue that the rejection of claim 1 should be reversed because Werner does not describe or suggest the claim limitation that requires the solar assembly to comprise “a flexible electric conductor materially bonded with the conductor path in an electrically conducting manner and materially bonded with the conductive strip in an electrically conducting manner.” Appeal Br. 12—14. We address each of Appellants’ arguments below. First, Appellants argue that the Examiner erred by finding that Werner describes or suggests an assembly having a flexible conductor that is materially bonded with the conductor path in an electrically conducting manner. Id. at 12. In rejecting claim 1, the Examiner found that Werner describes a flexible electric conductor that is connected to the conductor path in an electrically conducting manner. Final Act. 6. The Examiner acknowledges that “[t]he prior art fails to explicitly teach the electric conductor (41/45) being materially bonded with the conductor path (20) and materially bonded with the conductive strip (30).” Id. The Examiner continues: However, a skilled artisan reading the reference as a whole would readily appreciate that in the interconnection of these electrically conductive parts, the electric conductor (41/45) is materially bonded with the conductor path (20) and the conductive strip (30) with well-known and commonly used methods (soldering, resistance welding, etc.) as these are well- known connection techniques for a connection/circuit board. Further, it would have been obvious to one of ordinary skill in the art at the time of the invention to materially bond these 10 Appeal 2016-007496 Application 13/311,951 components as mechanical means for attachment provides stability to the device. Id. (emphasis added). As written, the Examiner’s analysis is internally inconsistent, in that after acknowledging that the prior art does not teach material bonding of the electric conductor to the conductor path, the Examiner then asserts that the electric conductor is materially bonded with the conductor path. When read in context, however, we conclude that the Examiner intended to state that a skilled artisan reading Werner as a whole would appreciate that the electric conductor could be materially bonded with the conductor path and the conductor strip. This is consistent with the Examiner’s Answer, where the Examiner states that [a] skilled artisan would readily appreciate the substituting of one known connection technique (clamping) for another known connection technique (soldering/welding/adhesive gluing). Further, one would recognize that solder/weld/glue has the advantage of a stronger connection point with a disadvantage of a permanent connection and that clamping has the advantage of easy snap-in assembly/disassembly with the disadvantage of a weaker connection point. Therefore, a skilled artisan would have [been] motivated to select any appropriate bonding technique based on the desired application of the final device and would have been willing to accept the consequent loss of [the] easy assembly/disassembly benefit that comes with the selection of solder/weld/glue for application^] where a strong connection point is a desired characteristic of the device. Answer 7. In response, Appellants argue that modifying Werner’s mechanical connection by replacing the clamp with soldering, welding, or gluing would defeat Werner’s intended purpose. Reply Br. 4. Appellants argue that Werner’s intended purpose is “to be able allow [sic, to allow] the two sets of 11 Appeal 2016-007496 Application 13/311,951 connecting elements to join one another when the connecting box is joined to the solar panel.” Id. Appellants’ argument is not persuasive of reversible error. The intended purpose of Werner’s assembly is to provide an electrical connection box for use on a backside-connected solar panel array. The Examiner’s proposed replacement of Werner’s with a clamped connection with a materially bonded connection does not prohibit this use, nor does it preclude the use of automated assembly procedures because welding robots are well known in the art. Second, Appellants argue that the Examiner erred by finding that Werner describes or suggests that the flexible conductor is materially bonded with the conductive strip in an electrically conducting manner. Appeal Br. 13. This argument is not persuasive of reversible error for the reasons discussed above. Third, Appellants argue that the Examiner erred by finding that Werner describes or suggests the use of a flexible electric conductor to connect the conductor path with the conductive strip. Appeal Br. 13—14. This argument is not persuasive of reversible error. Although Werner does not expressly describe the material from which fixed contacts 41 are fabricated, a person having ordinary skill in the art would have recognized that fixed contacts 41 would most likely be constructed of metal because they need to be electrically conductive. As discussed above, the proper interpretation of the claim term “flexible” is sufficiently broad that it encompasses thin metal parts such as fixed contacts 41. Furthermore, a person having ordinary skill in the art would have recognized that a small degree of lateral flexibility (as opposed to axial compressibility) would be 12 Appeal 2016-007496 Application 13/311,951 desirable to compensate for small amounts of misalignment between fixed contacts 41 and second contact elements 20. For the reasons set forth above, we affirm the rejection of claims 1 and 8 of the ’951 Application. Rejection 4. Appellants argue that the rejection of claim 9 should be reversed by virtue of claim 9’s dependence from claim 1. Appeal Br. 14. Because we have affirmed the rejection of claim 1, we also affirm the rejection of claim 9. Rejection 5. Appellants argue that the rejection of claims 2, 3, 6, and 7 should be reversed by virtue of these claims’ dependence from claim 1. Appeal Br. 14. Because we have affirmed the rejection of claim 1 as unpatentable over Werner, we cannot reverse the rejection of claims 2, 3, 6, and 7 as unpatentable over the combination of Werner and Hacke on that basis. Appellants also present separate, additional arguments for patentability of claims 2 and 7. Id. at 14—16. We address these arguments below. Claim 2. Claim 2 specifies that the flexible electric conductor of claim 1 is a woven wire mesh belt. In rejecting claim 2, the Examiner found that Hacke describes “known electrical conductor configuration [sic, configurations] such as conductor strips or wire mesh (abstract) comprising tin-coated (tinned) copper (paragraph [0049]).” Final Act. 8. Appellants argue that the rejection of claim 2 as unpatentable over the combination of Werner and Hacke should be reversed because the Examiner erred by concluding it would have been obvious to a person of ordinary skill in the art to use Hacke’s woven wire belt as the claimed flexible electric conductor. Appeal Br. 14—15. 13 Appeal 2016-007496 Application 13/311,951 We determine that the Examiner has not adequately demonstrated that the subject matter of claim 2 is unpatentable over the combination of Werner and Hacke. In particular, we note that Hacke describes the use of a woven wire mesh as the interconnecting structure with the solar cell. Hacke 150. In this use, the woven wire mesh corresponds to claim 1 ’s electrical conductive strip and not to the flexible electric conductor. The Examiner has not explained why a person of ordinary skill in the art at the time of the invention would have been motivated to use Hacke’s woven wire mesh as the flexible electric conductor. See In re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006) (“[r]ejections on obviousness grounds cannot be sustained by mere conclusory statements; instead, there must be some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness.”); In reRouffet, 149 F.3d 1350, 1358 (Fed. Cir. 1998) (“hindsight” is inferred when the specific understanding or principal within the knowledge of one of ordinary skill in the art leading to the modification of the prior art to arrive at appellant’s claimed invention has not been explained). Because we have reversed the rejection of claim 2, we also reverse the rejection of claims 3 and 6 which depend therefrom. Claim 7. Claim 7 specifies that the flexible electric conductor is materially bonded to the conductor path and to the conductive strip by resistance welding. The Examiner concluded that claim 7 adds product-by process limitations. Final Act. 8—9. The Examiner found that the structural limitations of claim 7 are met by the prior art and that Appellants have not demonstrated that resistance welding results in a product that is structurally different from the prior art. Id. In view of these findings, the Examiner 14 Appeal 2016-007496 Application 13/311,951 concluded that the subject matter of claim 7 is unpatentable over the combination of Werner and Hacke. Id. Appellants argue that this rejection should be reversed: The arguments set forth in section IV.C(3) above in regards to a comparison of independent claim 1 compared to Werner are incorporated with the term “resistance welded” being used in place of the term “materially bonded.” In view of the foregoing, claim 7 is separately patentable over Werner in view of Hacke. Appeal Br. 16. As discussed above, these arguments are not persuasive of reversible error. Thus, we affirm the rejection of claim 7 as unpatentable over the combination of Werner and Hacke. Rejection 6. Appellants argue that the rejection of claims 18—21 should be reversed by virtue of their dependence from claim 17. Appeal Br. 16. Because we have affirmed the rejection of claim 17 as anticipated by Rueggen, we cannot reverse the rejection of claims 18—21 as unpatentable over the combination of Rueggen and Hacke on that basis. Appellants also present separate, additional arguments for the patentability of claims 18 and 21. Id. at 16—18. We address these arguments below. Claim 18. Claim 18 specifies that the flexible electric conductor of claim 17 is a woven wire mesh belt. In rejecting claim 18, the Examiner found that Hacke describes “known electrical conductor configurations such as conductor strips or wire mesh (abstract) comprising tin-coated (tinned) copper (paragraph [0049]).” Final Act. 9. Appellants argue that the rejection of claim 18 as unpatentable over the combination of Rueggen and Hacke should be reversed because the 15 Appeal 2016-007496 Application 13/311,951 Examiner erred by concluding that it would have been obvious to use Hacke’s woven wire belt as the claimed flexible electric conductor. Appeal Br. 17-18. We reverse this rejection for the reasons expressed in connection with our reversal of the rejection of claim 2 as unpatentable over the combination of Werner and Hacke. Because we have reversed the rejection of claim 18, we also reverse the rejection of claims 19 and 20, which depend therefrom. Claim 21. Claim 21 specifies that the flexible electric conductor is materially bonded to the conductor path and to the conductive strip by resistance welding. The Examiner concluded that claim 21 adds product-by process limitations. Final Act. 9—10. The Examiner found that the structural limitations of claim 21 are met by the prior art and that Appellants have not demonstrated that resistance welding results in a product that is structurally different from the prior art. Id. In view of these findings, the Examiner concluded that the subject matter of claim 21 is unpatentable over the combination of Rueggen and Hacke. Id. Appellants argue that this rejection should be reversed: The arguments set forth in section IV.B(3) above in regards to comparison of independent claim 17 compared to Rueggen are incorporated with the term “resistance welded” being used in place of the term “materially bonded.” In view of the foregoing, claim 21 is separately patentable over Rueggen in view of Hacke. Appeal Br. 18. As discussed above, these arguments are not persuasive of reversible error. Thus, we affirm the rejection of claim 21 as unpatentable over the combination of Rueggen and Hacke. 16 Appeal 2016-007496 Application 13/311,951 CONCLUSION For the reasons set forth above, we reverse the rejection of claims 1—3 and 6—9 for failure to comply with the written description requirement. With respect to the prior art rejections, we affirm the rejection of claim 17 as anticipated by Rueggen. We also affirm the rejections of claims 1, 7—9, and 21 as unpatentable pursuant to § 103. Finally, we reverse the § 103 rejections of claims 2, 3, and 6 as unpatentable over the combination of Werner and Hacke and of claims 18—20 as unpatentable over the combination of Rueggen and Hacke. No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). AFFIRMED-IN-PART 17 Copy with citationCopy as parenthetical citation