@book { DieVolksschlerkonzerteinHamburg18981921,
    title = "Die Volksschülerkonzerte in Hamburg 1898-1921",
    author = "Elisabeth {Seippel}",
    year = "2012",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-02556-9",
    url = "https://www.peterlang.com/document/1047337"
}