@book { FreeSpeechTheory,
    title = "Free Speech Theory",
    author = "Helen J. {Knowles} and Brandon T. {Metroka}",
    year = "2020",
    publisher = "Peter Lang Verlag",
    address = "New York, United States of America",
    doi = "10.3726/b13431",
    url = "https://www.peterlang.com/document/1056967"
}