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Sociology in Bulgaria
Publishing House of the Bulgaria, 1970
 Buku Teks SO
Konstitusi Bulgaria
editor, S. Prajudi Atmosudirdjo ...[et al.]
Ghalia Indonesia, 1987
 Buku Teks
Bakels. H.L.
Arbeids wetgeving / H.L. Bakels
Kluwer, 1982
 Buku Teks
RED
Griffith University,
 Majalah, Jurnal, Buletin
Simsir, Bilal N.
The truks of Bulgaria (1878-1985)
K. Rustem & Brother, 1988
 Buku Teks SO