MLA

Henri, Robert, 1865-1929. "Paint" notebook with diagrams of color palettes and chords, and notes on the brush stroke, color, and backgrounds. Box 26, folder 599. n.d.. https://collections.library.yale.edu/catalog/17029595.

APA, 6th edition

Henri, Robert, 1865-1929. (["Box 26, folder 599"])(n.d.)["Paint" notebook with diagrams of color palettes and chords, and notes on the brush stroke, color, and backgrounds]. https://collections.library.yale.edu/catalog/17029595.