Oppenheim, Lassa (2005). International Law: A Treatise. The Lawbook Exchange. ISBN1-58477-609-9, 9781584776093 Periksa nilai: invalid character |isbn= (bantuan). Diakses tanggal 2008-10-05. At present there is no Personal Union in existenceParameter |coauthors= yang tidak diketahui mengabaikan (|author= yang disarankan) (bantuan)
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Lalor, ed. Various authors. See Contents. Cyclopaedia of Political Science. New York: Maynard, Merrill, and Co., ed. John Joseph Lalor, 1899. online versionDiarsipkan 2008-02-06 di Wayback Machine.; diakses 21 Juni 2008
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Lalor, ed. Various authors. See Contents. Cyclopaedia of Political Science. New York: Maynard, Merrill, and Co., ed. John Joseph Lalor, 1899. online versionDiarsipkan 2008-02-06 di Wayback Machine.; diakses 21 Juni 2008