Kautsky, John H.
John Wiley & Sons, 1967
Buku Teks
edited by Robert E. Ward & Dankward A. Rustews
Princeton University Press, 1968
Buku Teks
Helen Margetts, Perri 6, Christopher Hood, editors
Oxford University Press, 2012
Buku Teks
Dreyer, June Teufel, 1939-
Routledge, Taylor and Francis Group, 2019
Buku Teks
Canavan, Francis
Duke University Press, 1983
Buku Teks