@article{Rollik_1980,
    doi = {10.1007/bf00288647},
    url = {https://doi.org/10.1007%2Fbf00288647},
    year = {1980},
    month = {mar},
    publisher = {Springer Science and Business Media {LLC}},
    volume = {13},
    number = {3},
    pages = {287--298},
    author = {H. A. Rollik},
    title = {Automaten in planaren Graphen},
    journal = {Acta Informatica}
}

@article{Rollik_1980, doi = {10.1007/bf00288647}, url = {https://doi.org/10.1007%2Fbf00288647}, year = {1980}, month = {mar}, publisher = {Springer Science and Business Media {LLC}}, volume = {13}, number = {3}, pages = {287--298}, author = {H. A. Rollik}, title = {Automaten in planaren Graphen}, journal = {Acta Informatica} }