The Miriam and Ira D. Wallach Division of Art, Prints and Photographs: Photography Collection, The New York Public Library. "Isaac Newton, 1800-1867, first United States Commissioner of Agriculture." New York Public Library Digital Collections. Accessed January 16, 2017. http://digitalcollections.nypl.org/items/510d47d9-b209-a3d9-e040-e00a18064a99
New York Public Library
Cropped, sized, and prepared for use here by John Osborne, Dickinson College, January 16, 2017.
Humanities and Social Science Library, New York Public Library