Ulrich's international periodicals directory 1992-1993 : volume 2
R.R. Bowker, 1992
Buku Referensi
Ulrich's international periodicals directory 1990-1991 : volume 2
R. R. Bowker Company, 1990
Buku Referensi
Encyclopedia of associations : international organizations 1991, part 2
Gale Research, 1991
Buku Referensi
Directories in print 1991 : part 2
Gale Research, 1991
Buku Referensi
The Medical directory 1989 : part 2
Longman, 1989
Buku Referensi