Frick, Helen C.
MLA
Clapp, Frederick Mortimer, 1879-1969. Frick, Helen C.. Box 54. 1928-1943. https://collections.library.yale.edu/catalog/16593898.
APA, 6th edition
Clapp, Frederick Mortimer, 1879-1969. (["Box 54"])(1928-1943)[Frick, Helen C.]. https://collections.library.yale.edu/catalog/16593898.