by Dorothy Elhart [and others]
Mosby , 1978
Buku Teks
Barnes, Barry, author
Routledge & K. Paul, 1974
Buku Teks
Urwick, Lyndall F., author
Issac Pitman, 1957
Buku Teks
Gauch, Hugh G., 1942-, author
Cambridge University Press, 2012
Buku Teks
Ma Chung Press, 2009
Buku Teks