@book { WilliamofNassington,
    title = "William of Nassington",
    subtitle = "Canon, Mystic, and Poet of the Speculum Vitae",
    author = "Ingrid J. {Peterson}",
    year = "1986",
    publisher = "Peter Lang Verlag",
    address = "New York, United States of America",
    url = "https://www.peterlang.com/document/1078334"
}