MLA

Van Vechten, Carl, 1880-1964. Unidentified artist from Africa. Mask, undated, used as frontpiece for Black Ritual (Obeah), ballet choreographed by Agnes de Mille, music by Darius Milhaud. Box 223. 1953 August 12. https://collections.library.yale.edu/catalog/2019550.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 223"])(1953 August 12)[Unidentified artist from Africa. Mask, undated, used as frontpiece for Black Ritual (Obeah), ballet choreographed by Agnes de Mille, music by Darius Milhaud]. https://collections.library.yale.edu/catalog/2019550.