Wonder Woman #139 (DC, 1963 — Cover A)

When Steve Trevor is frustrated by Wonder Woman's refusal to marry him until all crime and injustice is erased from the Earth, he wishes aloud that she would forget who she is. Shortly thereafter, she destroys two enemy missiles by hurling them against each other and is caught in the explosion and knocked unconscious. Upon reviving, she flatly tells Steve that she is Diana Prince, and that Wonder Woman has lent her her costume for a masquerade ball she and Steve will be attending, but that she is not Wonder Woman.