POP has a core group of institutional collaborators who contribute provenance marks from their collections to the project and lend various forms of valuable support and advice to the project’s development. Collections represented, or soon to be represented, with provenance marks on POP include:
The Beinecke Library, Yale University
The Folger Shakespeare Library
The Getty Research Institute Special Collections Library
The Historical Society of Pennsylvania
The Library Company of Philadelphia
The Library of Congress, Rare Book and Special Collections Division
The Princeton University Rare Books and Special Collections Library