Peter MAX signed 1980 Democratic Convention Poster

Thrift shop find. It was in a broken frame with broken glass and covered in dust. Once I got it home I realized the poster itself was perfect with a pen signature by Max as well as a pencil signature from Dee Dee Ramone. After doing some research I learned that Dee Dee was an artist as well and friends with Max.
Its a great NY image and signed by two icons of the city. I had it reframed in a deco frame and it looks great. Paid 30 for the poster and way more to frame it!

Can't find the image anywhere on line...let me know if you have seen others for sale! Love to figure out the value!