Conquest, R.
Macmillan, 1960
Buku Teks
edited by Ralph S. Clem ; foreword by Edward Allworth
Frederick A. Praeger, 1975
Buku Teks SO
Riasanovsky, Nicholas V.
Oxford University Press, 1963
Buku Teks SO
Likhachev, Dmitrii S.
Westview Press, 1991
Buku Teks SO
Fainsod, Merle
Harvard University Press, 1956
Buku Teks SO