@book { TheUnbrokenCovenant,
    title = "The Unbroken Covenant",
    subtitle = "Could Ulster Unionists have controlled a nine-county Northern Ireland, 1920-1945?",
    author = "Samuel {Beckton}",
    year = "2025",
    publisher = "Peter Lang Verlag",
    address = "Oxford, United Kingdom",
    doi = "10.3726/b22808",
    url = "https://www.peterlang.com/document/1555777"
}