(by Victor Moscoso)
I bought ZAP Comix #13 in June 1994, probably in San Francisco, and got autographs from most of the cartoonists. I forgot all about the autographs until I was looking at the comic the other day!
On the front cover, Gilbert Shelton's autograph is in the lower left corner, vertically sideways. Robert Williams' personalized autograph is in the bottom center. (Victor Moscoso's signature (bottom right) is not an autograph; he's the cover artist and that's his pre-printed signature. He did autograph my copy on the inside. See below.)
On the inside cover, S. Clay Wilson's personalized and dated signature is across the top margin of the page.
On the first page, both Spain [Rodriguez] and Victor Moscoso signed along the right-hand margin of the page.
(Index of autographs)