Ballast, David Kent
Professional Publications, 2002
Buku Teks
Ballast, David Kent
Professional Publications, 1999
Buku Teks
Ballast, David Kent
Professional Publications, 2002
Buku Teks
Ballast, David Kent
McGraw-Hill, 1994
Buku Referensi
McCall, Ruth E.
Wolters Kluwer, 2016
Buku Teks