So they say

Chicago citation style
Smith, Harry Bache (1860-1936), Herbert, Victor (1859-1924). So they say. 1900. Retrieved from the Digital Public Library of America, http://digitalcollections.nypl.org/items/510d47df-ed65-a3d9-e040-e00a18064a99. (Accessed December 11, 2018.)
APA citation style
Smith, Harry Bache (1860-1936), Herbert, Victor (1859-1924), (1900) So they say. Retrieved from the Digital Public Library of America, http://digitalcollections.nypl.org/items/510d47df-ed65-a3d9-e040-e00a18064a99
MLA citation style
Smith, Harry Bache (1860-1936), Herbert, Victor (1859-1924). Retrieved from the Digital Public Library of America <http://digitalcollections.nypl.org/items/510d47df-ed65-a3d9-e040-e00a18064a99>.
Note: These citations are programmatically generated and may be incomplete.