Children's Book Materials and Other Writings
These include sketches, artwork, drafts, and prepress materials for over sixty published books, as well as unpublished materials. Also in the collection is a large group of thank yous and responses from schoolchildren and teachers, many in the form of artwork.
Personal and Family Materials
Of particular interest are documents from World War II: these comprise over 350 drawings done contemporaneously in Massachusetts, Scotland and France, as well as correspondence to his art-school classmate Eva Brussel.
Letters from ca. 1943 to the present with family, friends, and fans, and luminaries such as Pablo Casals and Robert Creeley
Drawings, sketches, and sketchbooks from numerous locations, including the Bronx, Maine, southern France, Freibourg Germany, and Antigua, as well as figurative and portrait studies.