@article{Lohrey_2007,
    doi = {10.1080/00927870601074855},
    url = {https://doi.org/10.1080%2F00927870601074855},
    year = {2007},
    month = {jan},
    publisher = {Informa {UK} Limited},
    volume = {35},
    number = {2},
    pages = {617--621},
    author = {Markus Lohrey and G{\'{e}}raud S{\'{e}}nizergues},
    title = {When Is a Graph Product of Groups Virtually-Free?},
    journal = {Communications in Algebra}
}

@article{Lohrey_2007, doi = {10.1080/00927870601074855}, url = {https://doi.org/10.1080%2F00927870601074855}, year = {2007}, month = {jan}, publisher = {Informa {UK} Limited}, volume = {35}, number = {2}, pages = {617--621}, author = {Markus Lohrey and G{\'{e}}raud S{\'{e}}nizergues}, title = {When Is a Graph Product of Groups Virtually-Free?}, journal = {Communications in Algebra} }