* "Sign Language Among North American Indians Compared With That Among Other Peoples And Deaf-Mutes," "First Annual Report of the Bureau of Ethnology to the Secretary of the Smithsonian Institution, 1879-1880", Government Printing Office, Washington, 1881, pages 263-552* Clark, William Philo.
* "Sign Language Among North American Indians Compared With That Among Other Peoples And Deaf-Mutes," "First Annual Report of the Bureau of Ethnology to the Secretary of the Smithsonian Institution, 1879-1880", Government Printing Office, Washington, 1881, pages 263-552* Clark, William Philo.