@book { WirklichkeitstheaterStrassentheaterFreiesTheater,
    title = "Wirklichkeitstheater, Strassentheater, Freies Theater",
    subtitle = "Entstehung und Entwicklung freier Gruppen in der Bundesrepublik Deutschland 1968-76",
    author = "Barbara {Büscher}",
    year = "1987",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1075511"
}