Every licensed doctor of optometry whose name or office address or place of practice appears or is mentioned in any advertisement of any kind or character shall be presumed to have caused, allowed, permitted, approved, and sanctioned such advertising and shall be presumed to be personally responsible for the content and character thereof. Once sufficient evidence of the advertisement's existence has been introduced at any administrative hearing before the board of optometry, the burden of proof to rebut this presumption by a preponderance of the evidence shall be upon the doctor of optometry.