USA
1968 February - April
Several Marvel Comics series published a full-page We're Only In It For The Money advertisement between February and April 1968.
Source: slime.oofytv.set
The Spectacular Spider-Man was initially a two-issue magazine published by Marvel in 1968, as an experiment in entering the black-and-white comic-magazine market successfully pioneered by Warren Publishing and others. It sold for 35 cents when standard comic books cost 12 cents and annuals and giants 25 cents. It represented the first Spider-Man spin-off publication aside from the original series' summer annuals, begun in 1964. (wikipedia)
Full page We're Only In It For The Money ad. No more Zappa-related content.
Source: slime.oofytv.set