MLA

Howe, Susan, 1937-. Erratics / Perpetual Snow Fields. 24 (Broadside). Late 1970s-early 1980s. https://collections.library.yale.edu/catalog/16852898.

APA, 6th edition

Howe, Susan, 1937-. (["24 (Broadside)"])(Late 1970s-early 1980s)[Erratics / Perpetual Snow Fields]. https://collections.library.yale.edu/catalog/16852898.