Scott, W. D. (1908). The unconscious influence in street railway advertising. In W. D. Scott, The psychology of advertising: A simple exposition of the principles of psychology in their relation to successful advertising (pp. 215-225). Boston, MA, : Small, Maynard & Company.
http://dx.doi.org/10.1037/13645-015
Every form of advertising has its particular psychological effect, and the medium which the merchant should choose depends upon many conditions. The psychological effect of street car advertising is not generally recognized and in this presentation there is no attempt to praise one form of advertising and to decry all others, but inasmuch as the psychological effects of other forms are recognized and that of street car advertising is frequently not recognized, this latter is selected for fuller presentation. (PsycINFO Database Record (c) 2016 APA, all rights reserved)