Washington : Pan American Union, General Secretariet of the Organization of American States
Majalah, Jurnal, Buletin
Clair, Guy St.
Bowker, 1996
Buku Teks
edited by Peter Smyth
Institution of Engineering and Technology, 2008
eBooks
Scheer, August-Wilhelm
Springer-Verlag, 1994
Buku Teks
Green Press, 2003
Buku Teks