The number "628" in white ink appears on verso. This number has been scratched on the glass negative and a further number, "584" is on the negative but not on the albumen print in the Nelson collection.
A glass negative of this image is located in the Myron Bement Smith Collection. Freer Gallery of Art and Arthur M. Sackler Gallery Archives. Smithsonian Institution, Washington, D.C. The reference number for the negative is FSA A.4 2.12.GN.31.01.