J. M.  Greenman, ?New and otherwise noteworthy Angiosperms from Mexico and Central America?, Proceedings of the American Academy of Arts and Sciences, vol. 39, pp. 67 - 120, 1903.

J. J.  Smith, Icones Bogoriensis, vol. 2. Leiden: Brill, 1903, pp. 1 - 328.

T. D. A.  Cockerell, ?Two orchids from New Mexico?, Torreya, vol. 3, pp. 139 - 141, 1903.