Thompson, Janice, author
Pearson, 2016
Buku Teks
edited by Fabrizio Fabris, Luigi Pernigotti and Ermanno Ferrario
Raven Press, 1990
Buku Teks
edited by Jane B.Morgan, John W.T.Dickerson,
John Wiley & Sons, 2003
Buku Teks
Beal, Virginia A.
Macmillan, 1986
Buku Teks
Alford, Betty B.
Prentice-Hall, 1982
Buku Teks