Home › Authors › Pieter Jan Kuijper 👤 Pieter Jan Kuijper 3 books Books by Pieter Jan Kuijper From Treaty-Making to Treaty-B From Treaty-Making to Treaty-Breaking 2015 Of 'Mixity' And 'Double-hattin Of 'Mixity' And 'Double-hatting' 2008 Law of the European Union and Law of the European Union and the European Communities 2006