See P. P. Remec, The Position of the Individual in International Law (1960).
Vattel's masterpiece was largely influenced by The Law of Nations by Christian Wolff. His work began, in fact, by translating Wolff's text from its Latin into the vernacular and adding his own thoughts. The work was also heavily influenced by Gottfried Leibniz and Hugo Grotius. Focused largely on the rights and obligations of citizens and states, the work also had ramifications for Just War Theory as it outlined international diplomacy as we now know it. Vattel elucidated the "Golden Rule of Sovereigns": One cannot complain when he is treated as he treats others.
The work is available online at Online Library of Liberty
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