@article{Tiuryn_2002,
    doi = {10.1006/inco.2001.2950},
    url = {https://doi.org/10.1006%2Finco.2001.2950},
    year = {2002},
    month = {nov},
    publisher = {Elsevier {BV}},
    volume = {179},
    number = {1},
    pages = {1--18},
    author = {Jerzy Tiuryn and Pawe{\l} Urzyczyn},
    title = {The Subtyping Problem for Second-Order Types Is Undecidable},
    journal = {Information and Computation}
}

@article{Tiuryn_2002, doi = {10.1006/inco.2001.2950}, url = {https://doi.org/10.1006%2Finco.2001.2950}, year = {2002}, month = {nov}, publisher = {Elsevier {BV}}, volume = {179}, number = {1}, pages = {1--18}, author = {Jerzy Tiuryn and Pawe{\l} Urzyczyn}, title = {The Subtyping Problem for Second-Order Types Is Undecidable}, journal = {Information and Computation} }