United Nations, 1992
Buku Referensi
edited by John E. Simkin
D.W. Thorpe, 1993
Buku Referensi
edited by Angel Aparicio
University of Santo Tomas, 2001
Buku Referensi
editor, Angel Aparicio
University of Santo Tomas, 2006
Buku Referensi
editor, Angel Aparicio
University of Santo Tomas, 2005
Buku Referensi