"Happy New Year!"
MLA
Hansen, Bert, 1944-. "Happy New Year!". Box 11, folder 25. 1908 December 30. https://collections.library.yale.edu/catalog/32326830.
APA, 6th edition
Hansen, Bert, 1944-. (["Box 11, folder 25"])(1908 December 30)["Happy New Year!"]. https://collections.library.yale.edu/catalog/32326830.