Greenbaum, Sidney
Longman , 1990
Buku Teks
Helling, Pam, author
[American Management Association, ], 1992
eBooks
CHalker, Sylvia, author
Clarendon Press, 1994
Buku Referensi
Huddleston, Rodney, author
Cambridge University Press, 1984
Buku Teks
Collins, Peter, author
Palgrave Macmillan, 2020
Buku Teks