Article 30 [Prohibition of New Customs Duties or Charges Having Equivalent Effect]Kerikmäe, Tanel; Särav, SandraTreaty on the Functioning of the European Union - A Commentary2021 / p. 711-718 https://doi.org/10.1007/978-3-030-43511-0_31

Article 33 [Customs Cooperation]Kerikmäe, Tanel; Särav, Sandra; Hamulak, OndrejTreaty on the Functioning of the European Union - A Commentary2021 / p. 733-736 https://doi.org/10.1007/978-3-030-43511-0_34

Commentaries on Article 32 TFEU on Principles Guiding the Commission in the Exercise of its Functions relating to the Customs UnionHoffmann, Thomas; Kerikmäe, TanelSmit & Herzog on The Law of the European Union2016 / p. 32-1-32-4