APA
Degan V D,, . (1997). Sources of international law. London: Martinus Nijhoff Publishing Ltd.
Chicago
Degan V D,, . 1997. Sources of international law. London: Martinus Nijhoff Publishing Ltd.
Harvard
Degan V D,, . (1997). Sources of international law. London: Martinus Nijhoff Publishing Ltd.
MLA
Degan V D,, . Sources of international law. London: Martinus Nijhoff Publishing Ltd. 1997.