@book { DerSchulleiteralsIntrapreneur, title = "Der Schulleiter als Intrapreneur", author = "Nicole {Follmer}", year = "2015", publisher = "Peter Lang Verlag", address = "Berlin, Germany", doi = "10.3726/978-3-653-05502-3", url = "https://www.peterlang.com/document/1049153" }