Smyrl, J.L., author
Hodder and Stoughton, 1978
Buku Teks
Whitehead, Alfred North, 1861-1947, author
Oxford University Press, 1969
Buku Teks
Lister, Frederick M., author
Prentice-Hall, 1966
Buku Teks
Strang, Gilbert, author
Wellesley Cambridge Press, 1986
Buku Referensi
Keedy, Mervin J., author
Addison-Wesley , 1969
Buku Teks