Barrios-Lech, Peter, 1977-, author
Cambridge University Press, 2016
Buku Teks
Epstein, Charlotte, author
Prentice-Hall, 1974
Buku Teks
Williams, Christine L., author
Jones and bartlett , 2008
Buku Teks
The Free Press, 1972
Buku Teks
Collins, Orvis, author
Mouton, 1973
Buku Teks