@article{Grohe_2012,
    doi = {10.1145/2371656.2371662},
    url = {https://doi.org/10.1145%2F2371656.2371662},
    year = {2012},
    month = {oct},
    publisher = {Association for Computing Machinery ({ACM})},
    volume = {59},
    number = {5},
    pages = {1--64},
    author = {Martin Grohe},
    title = {Fixed-point definability and polynomial time on graphs with excluded minors},
    journal = {Journal of the {ACM}}
}

@article{Grohe_2012, doi = {10.1145/2371656.2371662}, url = {https://doi.org/10.1145%2F2371656.2371662}, year = {2012}, month = {oct}, publisher = {Association for Computing Machinery ({ACM})}, volume = {59}, number = {5}, pages = {1--64}, author = {Martin Grohe}, title = {Fixed-point definability and polynomial time on graphs with excluded minors}, journal = {Journal of the {ACM}} }