Citation
L. H. Wilder. [1910]. “An open-backed surface privy, figure for "The Sanitary Privy" by C. W. Stiles (1911), U.S. Department of Agriculture Farmers' Bulletin 463..” Special Collections, USDA National Agricultural Library. Accessed February 17, 2025, https://www.nal.usda.gov/exhibits/speccoll/items/show/8102.