Hackel, Betty letter to Chase, Mary Agnes Merrill (1869–1963) with translation, 17 February 1926, Box: 5, Folder: 60. William Winfield Ray collection of 20th century botanists correspondence and other materials, HIBDARC-0048. Hunt Institute for Botanical Documentation Archives. https://as.huntbot.org/repositories/2/archival_objects/4394 Accessed March 20, 2026.