@incollection{HoefnerMoeller2020,
  author    = {Peter H{\"o}fner and Bernhard M{\"o}ller},
  title     = {Extended feature algebra [Extended Abstract]},
  booktitle = {Proceedings of the First International Workshop on Feature-Oriented Software Development (FOSD), October 6, 2009, Denver, Colorado, USA},
  editor    = {Sven Apel and William R. Cook and Krzysztof Czarnecki and Christian K{\"a}stner and Neil Loughran and Oscar Nierstrasz},
  isbn      = {978-1-60558-567-3},
  url       = {https://www.infosun.fim.uni-passau.de/spl/apel/FOSD2009/},
  year      = {2020},
}