@bookPart{Giegerich_2018,
title={Article 61 : Supervening impossibility of performance},
author={Giegerich, Thomas},
editor={Dörr, Oliver and Schmalenbach, Kirsten},
isbn={978-3-662-55160-8},
doi={http://dx.doi.org/10.22028/D291-30835},
adress={Berlin},
pages={1127-1142},
publisher={Springer},
booktitle={Vienna Convention on the Law of Treaties : a commentary},
year={2018}
}