H. Ellsworth Ewing, ?The identity and variation of Pediculus humanus americanus?, Proceedings of the Helminth Society of Washington, vol. 3, no. 1, pp. 36 - 37, 1936.

H. Ellsworth Ewing, ?Two new pre-columbian records of the American head louse, Pediculus humanus americanus?, Proceedings of the Helminth Society of Washington, vol. 2/2, pp. 67 - 68, 1935.