Wolfgang Sonntag manuscripts (HC.MC.975.07.111), Quaker & Special Collections, Haverford College, Haverford, PA.
Wolfgang Sonntag manuscripts (HC.MC.975.07.111), Quaker & Special Collections, Haverford College, Haverford, PA. https://archives.tricolib.brynmawr.edu//repositories/5/resources/1047 Accessed February 10, 2025.
