MLA

Erdoes, Richard, 1912-2008. Procession Long. Box 66 | Las Golondrinas; Mountain Crosses. 1976-1983, undated. https://collections.library.yale.edu/catalog/2091747.

APA, 6th edition

Erdoes, Richard, 1912-2008. (["Box 66 | Las Golondrinas; Mountain Crosses"])(1976-1983, undated)[Procession Long]. https://collections.library.yale.edu/catalog/2091747.