@book { DieEntwicklungvonPostponementRckblickGegenwartundAusblick,
    title = "Die Entwicklung von Postponement - Rückblick, Gegenwart und Ausblick",
    author = "Bruno {Bellovoda}",
    year = "2011",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783842809727",
    url = "https://m.diplom.de/document/228261"
}