Khurmi, R. S., author
Eurasia Publishing House, 1980
Buku Teks
Movnin, M.
Moscow: Mir Publishers, 1975
Buku Teks
Wilson, Charles E., author
Prentice-Hall, 1997
Buku Teks
Spotts, M.F. (Merhyle Franklin), author
Prentice-Hall, 1985
Buku Teks
Jain, Rajendra K., author
Khanna Publishers, 1983
Buku Teks