Book excerpt: Although, according to the author, much sound research, has been done in the Dufay era in recent years," Charles Hamm's book marks the first time an attempt has been made at a comprehensive chronology of the works of this composer. Professor Hamm approaches all Dufay’s compositions from the point of view of mensural practice, and has been able to date each piece more precisely than would have been possible in a chronology based on manuscript studies or stylistic analyses. He has divided the works into nine groups, according to details of mensural usage, and on the basis of datable works and other evidence has suggested dates within which the pieces of each group were written. Based on his study of Dufay’s mensural practice, the author suggests that the Missa Sancti Antoni and several other works attributed to Dufay may not have been written by him. Originally published in 1964. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.