"Civilization's Next Step" (HC.MC.975.07.105), Quaker & Special Collections, Haverford College, Haverford, PA.
"Civilization's Next Step" (HC.MC.975.07.105), Quaker & Special Collections, Haverford College, Haverford, PA. https://archives.tricolib.brynmawr.edu//repositories/5/resources/1011 Accessed December 12, 2024.