Goch, Desmond
Pan Books , 1971
Buku Teks
Fields, Edward, author
[American Management Association;, ], 2011
eBooks
White, Robert W., author
Prentice-Hall, 1996
Buku Teks
Collin, P. H., author
Peter Collin Publishing, 2001
Buku Teks
Block, Stanley B., author
Canfield Press, 1973
Buku Teks