[1898] - Washington Irving Lincoln Adams (1865-1946), In Nature's image. Chapters on pictorial photography, Baker & Taylor, NY 1898, chap. 6, pp. 61-70.
[1898] - Robert H. Hobart Cust (1861-1940), The nude, "The photogram", V 1898, pp. 283-286, p. 286.
[1899] - Fritz Loescher, Über Kunstphotographie, "Das Atelier des Photographen", VI 1899, pp. 195-200.