@incollection{Karpinski_1988,
    doi = {10.1007/3-540-50241-6_34},
    url = {https://doi.org/10.1007%2F3-540-50241-6_34},
    year = {1988},
    publisher = {Springer Berlin Heidelberg},
    pages = {129--137},
    author = {Marek Karpinski and Hans Kleine Büning and Peter H. Schmitt},
    title = {On the computational complexity of quantified Horn clauses},
    booktitle = {Lecture Notes in Computer Science}
}

@incollection{Karpinski_1988, doi = {10.1007/3-540-50241-6_34}, url = {https://doi.org/10.1007%2F3-540-50241-6_34}, year = {1988}, publisher = {Springer Berlin Heidelberg}, pages = {129--137}, author = {Marek Karpinski and Hans Kleine Büning and Peter H. Schmitt}, title = {On the computational complexity of quantified Horn clauses}, booktitle = {Lecture Notes in Computer Science} }