A show of Diebeenkorn's work just closed yesterday in Sonoma, but it looks like Stanford will soon display a group of recently acquired Diebenkorn sketchbooks, starting in September.
Richard Diebenkorn: The Sketchbooks Revealed will be showing September 9 to February 8, 2016 at the
Cantor Arts Center at Stanford University (328 Lomita Drive at Museum Way, Stanford, California).