Stevenson, Edward J.
Noyes Data Corporation, 1977
Buku Teks
Swarup, D.
Rakesh K. Rastogi for Rastogi, 1981
Buku Teks
Cottrell, Alan
ELBS/Edward Arnold, 1975
Buku Teks
Higgins, Raymond.A.
E. Arnold,, 1980
Buku Teks
Rollason, E.C.
Edward Arnold, 1978
Buku Teks