i did these with linoleum block printing. some of them were done on this stuff that's kind of like acetate but not as slick, and some were done on velum (sp?). i did some black ones and some pink ones.
you can see the outline of a clear sheet...i just don't know if all of them were printed on those clean sheets, or if he used it to photograph, and then printed the photo on regular paper. i'm kinda hoping he printed everything on clear sheets, but either way it's very niceley done...mainly because the text is done in a really compelling way.