Bruggencate, K. Ten, author
J.B. Wolters-Groningen, [Date of publication not identified]
Buku Referensi
Ettin, Mark F.
Allyn and Bacon, 1992
Buku Teks
Engels, Friedrich, 1820-1895, author
Fereign Languages Publishing House, 1954
Buku Teks
Lenin, Vladimir I., author
Foreign Languages Publishing House, 1953
Buku Teks
Stepanova, Yelena Mikhaylovna, author
Foreign languages Publishing House , 1958
Buku Teks