MLA

Lindbergh, Charles A. (Charles Augustus), 1902-1974. Diaries, 1912-1939 May 9. Box 207, folder 415-434. 1912-1939 May 9. https://collections.library.yale.edu/catalog/10013982.

APA, 6th edition

Lindbergh, Charles A. (Charles Augustus), 1902-1974. (["Box 207, folder 415-434"])(1912-1939 May 9)[Diaries, 1912-1939 May 9]. https://collections.library.yale.edu/catalog/10013982.