Cuthbert, Mike
Cavendish Publishing Limited, 1993
Buku Teks
Belgium : R.H. Wijffels, 1972
Buku Teks
Jans, Jan H.
Europa Law Publishing, 2000
Buku Teks
Blaipain, Roger
Kluwer Law International, 2008
Buku Teks
Terra, Ben J.M.
Wolters Kluwer, 2008
Buku Teks