MLA

Schwartz, Delmore, 1913-1966. Various poems from insert to The Library of Congress Twentieth Century Poetry in English recordings. Box 4, folder 250. 1954. https://collections.library.yale.edu/catalog/17405253.

APA, 6th edition

Schwartz, Delmore, 1913-1966. (["Box 4, folder 250"])(1954)[Various poems from insert to The Library of Congress Twentieth Century Poetry in English recordings]. https://collections.library.yale.edu/catalog/17405253.