Cite

A2 Bg9 3 - A2 Mf4 Sh2

MLA

Oastler, Frank Richard, 1871-1936. A2 Bg9 3 - A2 Mf4 Sh2. Box 83, folder 87. 1927-1935, undated. https://collections.library.yale.edu/catalog/2040510.

APA, 6th edition

Oastler, Frank Richard, 1871-1936. (["Box 83, folder 87"])(1927-1935, undated)[A2 Bg9 3 - A2 Mf4 Sh2]. https://collections.library.yale.edu/catalog/2040510.