In using the title "doctor" as a trade or professional asset or on any manner of professional identification, including a sign, pamphlet, stationery, or letterhead, or as a part of a signature, a person other than a person described by Section 104.003 shall designate the authority under which the title is used or the college or honorary degree that gives rise to the use of the title.
Tex. Occ. Code § 104.004