The proceedings of the ABZ 2020 are published as Springer LNCS volume 12071: https://link.springer.com/book/10.1007/978-3-030-48077-6 ABZ 2021 will take place from June, 9-11 2021. More information and a new call for papers can be found on the new website https://abz2021.uni-ulm.de.
