MLA

Lindbergh, Charles A. (Charles Augustus), 1902-1974. Correspondence. Box 89, folder 65-68. 1959-1973, undated. https://collections.library.yale.edu/catalog/10014637.

APA, 6th edition

Lindbergh, Charles A. (Charles Augustus), 1902-1974. (["Box 89, folder 65-68"])(1959-1973, undated)[Correspondence]. https://collections.library.yale.edu/catalog/10014637.