"The National Cyclopædia of American Biography: Being the History of the United States as Illustrated in the Lives of the Founders, Builders, and Defenders of the Republic, and of the Men and Women who are Doing the Work and Moulding the Thought of the Present Time". 1969. https://books.google.com/books?id=cDIOAQAAMAAJ&q=Burr+Shafer+1899
"Milestones: Jun. 25, 1965". Time. June 25, 1965. Archived from the original on February 3, 2011. https://web.archive.org/web/20110203174558/http://www.time.com/time/magazine/article/0,9171,833816,00.html
E.g. Through History with J. Wesley Smith and its sequels.
"Milestones: Jun. 25, 1965". Time. June 25, 1965. Archived from the original on February 3, 2011. https://web.archive.org/web/20110203174558/http://www.time.com/time/magazine/article/0,9171,833816,00.html
"'Women's Auxillary [sic]' Burr Shafer Original panel cartoon". Comic Cartoons Webportfolio. The Art-cade Gallery. http://www.artcadeonline.com/artwork/comic/detail.asp?ID=1265
Haverstick, John (1957). "The Saturday Review" Treasury: A Volume of Good Reading Selected from the Complete Files by John Haverstick and the Editors of the Saturday Review. New York: Simon and Schuster. p. 493. OCLC 193181. https://www.questia.com/PM.qst?a=o&d=282779
"Milestones: Jun. 25, 1965". Time. June 25, 1965. Archived from the original on February 3, 2011. https://web.archive.org/web/20110203174558/http://www.time.com/time/magazine/article/0,9171,833816,00.html