@book { CarlHagenbeck18441913,
    title = "Carl Hagenbeck (1844-1913)",
    author = "Lothar {Dittrich} and Annelore {Rieke-Müller}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1087912"
}