@book { BulgarischeSpracheLiteraturundGeschichteBulgarischeSammlungBd1,
    title = "Bulgarische Sprache, Literatur und Geschichte (= Bulgarische Sammlung, Bd. 1)",
    author = "Wolfgang {Gesemann} and Kyrill {Haralampieff} and Helmut {Schaller}",
    year = "1980",
    publisher = "Biblion",
    address = ", Germany",
    doi = "10.3726/b12586",
    url = "https://www.peterlang.com/document/1067036"
}