MLA

Steinberg, Saul, 1914-1999. "T" General. Box 48, folder 867-868 | Box 49, folder 869-873. 1944-1995, undated. https://collections.library.yale.edu/catalog/10545530.

APA, 6th edition

Steinberg, Saul, 1914-1999. (["Box 48, folder 867-868 | Box 49, folder 869-873"])(1944-1995, undated)["T" General]. https://collections.library.yale.edu/catalog/10545530.