“The School Journal” Vol. 51. No. 3, subtitle of “Department of State Educational Association: Conference on Nature Study.” , 1902-09-01, Box: 1, Folder: 2. Albert E. Maltby Collection, 3-2. Slippery Rock University Archives and Special Collections. http://as-slippery.klnpa.org/repositories/2/archival_objects/12506 Accessed May 23, 2026.