Book: Belden, Louise C. 1980 Marks of American Silversmiths in the Ineson-Bissell Collection. 506 p.
• An illustrated glossary of spoon terms, pp. 467-488Book: Belden, Louise C. 1980 Marks of American Silversmiths in the Ineson-Bissell Collection. 506 p.
• Information on William Seal Jr., p. 377Book: McGrew, John R. 2004 Manufacturers' Marks on American Coin Silver. 176.
• Description of mark and possible background information, p. 111Book: McGrew, John R. 2004 Manufacturers' Marks on American Coin Silver. 176.
• Information on William Seal Jr., p. 111Book: McGrew, John R. 2004 Manufacturers' Marks on American Coin Silver. 176.
• Information on John McMullin, p. 102Book: Currier, Ernest M. 1938 Marks of Early American Silversmiths: With Notes on Silver, Spoon Types & List of New York City Silversmiths 1815-1841. 179 p.
• Biographical information on John McMullin, p. 94Book: Currier, Ernest M. 1938 Marks of Early American Silversmiths: With Notes on Silver, Spoon Types & List of New York City Silversmiths 1815-1841. 179 p.
• Biographical information on William Seal Jr., p. 127Book: Buhler, Kathryn C. & Hood, Graham. 1970 American Silver: Garvan and Other Collections in the Yale University Art Gallery.
• Information on John McMullin, vol. II, pp. 201, 204Book: Ensko, Stephen G. C. 1948 American Silversmiths and Their Marks III. 285 p.
• Biographical information on William Seal Jr., p. 118