Creighton, Donald, author
Macmillan, 1981
Buku Teks
Shaw, A.G.L. (Alan George Lewers), author
Faber and Faber, 1955
Buku Teks
by Donella H. Meadows ... [and others]
Universe Books, 1972
Buku Teks
Harlow, Ralph Volney, author
Holt, Rinehart and Winston,Inc, 1964
Buku Teks
McCrum, Robert
Faber and Faber , 1992
Buku Teks