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Charles Schulz's limited edition lithographs bring auction values between $800-2,000 when sold in a dedicated Illustration or Comic Art sale; as one might imagine, there are fewer artist proof lithos that have come to auction and the ones I've found have sold - somewhat surprisingly, though not in a specialized sale - for LESS than his limited edition lithograps do. I think this has greater merit than that and have evaluated accordingly.
Based on the photos and information provided, and subject to examination, this is:

Charles Monroe Schulz (American, 1922-2000)
Untitled artist's proof lithograph ("Auuuggghhh)
pencil inscribed AP lower left and signed lower right
accompanied by a Certificate of
12 by 16 inches unframed
CONDITION: appears to be in good condition, matted and framed
PROVENANCE: Cordelia and Tom Platt, Autographs & Historic Material, Ft. Lauderdale FL
$1,000-2,000*
*represents a fair-market value for auction purposes; retail or asking price may vary.

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