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        There's a collection of Warner Bros. cartoons that is devoted to
this called, I think "Hooray for Hollywood," but this is so common in
Warner Bros. cartoons that looking though any of their (many) anthology
tapes or laserdisc collections would turn up examples.  Collections of
Betty Boop cartoons would do the same to some extent: she imitates various
30s stars in her cartoons.  Hank Sartin, who's out there somewhere on the
net (and who is at the University of Chicago in real space) is currently
working on this topic, so he would know all the examples.