During the 1940’s, Ann Nolan Clark, who worked for the BIA, published a couple children’s books that were translated by Robert Young and J.P. Harrington. This is just one of several projects that Young and Harrington collaborated on. For example, other materials related to Harrington’s writing include notes for his “Southern Peripheral Athapaskan Origins, Divisions, and Migrations” and preliminary drafts and notes for the Navajo portion of “Earliest Navaho and Quechua” (1944) coauthored by Robert W. Young. (https://collections.si.edu/search/detail/edanmdm:siris_arc_363476)
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“In the autumn of 1937, Young (who was now working at Fort Wingate at the Southwestern Range and Sheep Breeding Laboratory) developed the official government orthography together with his Navajo co-worker William P. Morgan, and Harrington, with the help of the anthropologist and novelist Oliver LaFarge. This orthography was used in reading and teaching materials in the spring of 1940, and a number of primers and school readers were produced.” (Spolsky 2009)