APA
Villiger M. E., . (2009). Commentary on the 1969 Vienna Convention on the Law of Treaties. Boston: Martinus Nijhoff Publishers.
Chicago
Villiger Mark Eugen, . 2009. Commentary on the 1969 Vienna Convention on the Law of Treaties. Boston: Martinus Nijhoff Publishers.
Harvard
Villiger M. E., . (2009). Commentary on the 1969 Vienna Convention on the Law of Treaties. Boston: Martinus Nijhoff Publishers.
MLA
Villiger Mark Eugen, . Commentary on the 1969 Vienna Convention on the Law of Treaties. Boston: Martinus Nijhoff Publishers. 2009.