Sidney B. Felsen is the co-founder of the legendary artist’s workshop Gemini G.E.L., established with Stanley Grinstein in 1966. Since then, he has nurtured the collaborations that take place in the printmaking studio. He has worked with artists including Baldessari, Bell, Chamberlain, Diebenkorn, Guston, Hockney, Johns, Kelly, Lichtenstein, Nauman, Rothenberg, Ruscha, Stella, and Tuttle among