Other information: Martin owned the original mounted portrait, which was passed down the family line. The words "Campbell Studio / Waldorf Astoria" are imprinted in the lower right corner. It's viewable below under "file history" (framed picture) when enlarged to maximum size. Hence, the portrait dates to between 1911 & 1913. The studio was located inside the former Waldorf-Astoria hotel, for only those three years. Sources: 1a) Trow Business Directory of the Boroughs of Manhattan and the Bronx, 1913 p. 785 (address listing). 1b) Studio Light, Eastman Kodak Company, March 1917 p. 12. Excerpt: "In 1911, the Campbell Studio opened spacious quarters in the Waldorf Astoria, but after three years found that they needed more room to carry on an ever-increasing business, so moved to their present location at 538 Fifth Avenue." Internet Archive. 1c) American Art Annual, edited by Florence Nightingale Levy, 1914 p. 514. The company's address is now 538 Fifth Avenue. HathiTrust.

Connection. Who's Who in America 1912-1913, edited by Albert Nelson Marquis, 1912 p. 633. This is a primary source that connects Eickemeyer to the historic hotel. His work address is given as "Campbell Studio, Waldorf-Astoria, New York, N.Y." Who's Who in New York City and State, edited by William Frederick Mohr, 1914 pp. 229–30. Backup source. Who's Who in America 1920-1921, p. 862. His second stint with Campbell Studio was from 1911–15.

This work was never published prior to January 1, 2003, and is currently in the public domain in the United States because it meets one of the following conditions: its author died before 1954; the death date of its author is not known, and it was created before 1904; it is an anonymous work, a pseudonymous work, or a work made for hire, and it was created before 1904. The above provisions are contained in 17 U.S.C. § 303. See also this page for more information.