Ulrich's international periodicals directory 1990-1991 : volume 1
R. R. Bowker Company, 1990
Buku Referensi
Ulrich's international periodicals directory 1991-1992 : volume 1
R.R. Bowker, 1991
Buku Referensi
Directory of population periodicals of the ESCAP Regional Population Information Centre, 1986
Bangkok : Population Division,ESCAP, 1986, 1986
Buku Referensi
Ulrich's international periodicals directory 1991-1992 : volume 2
R.R. Bowker, 1991
Buku Referensi
Ulrich's international periodicals directory 1991-1992 : volume 3
R.R. Bowker, 1991
Buku Referensi