Hinkel, Eli
Baron's, 1994
Buku Referensi
Lusin, Natala
Baron's Education, 1992
Buku Referensi
compiled by O.S. Akhmanova ... [and others]
Foreign and National, 1959
Buku Referensi
Wade, Terence, author
Cambridge University Press, 2009
Buku Teks
Raptschinsky, Boris, author
E.J. Brill, 1952
Buku Referensi