Trott, Paul, author
Pearson Education , 2017
Buku Teks
Bryson, George D.
Harper & Brothers, 1961
Buku Teks
McLeod, T. S.
Gower Press, 1971
Buku Teks
Chambers, John C. (John Carlton), 1928-, author
John Wiley & Sons, 1974
Buku Teks
Andrews, Kenneth R., author
Harvard University , 1966
Buku Teks