Ware (2000), p. 18 Ware, Susan (2000). Forgotten Heroes: Inspiring American Portraits from Our Leading Historians. Portland, OR: Simon and Schuster. ISBN978-0-684-86872-1. OCLC45179918.
Ware (2000), pp. 19–24 Ware, Susan (2000). Forgotten Heroes: Inspiring American Portraits from Our Leading Historians. Portland, OR: Simon and Schuster. ISBN978-0-684-86872-1. OCLC45179918.