@book { RohrvortriebssystemeDN800,
    title = "Rohrvortriebssysteme DN <= 800",
    author = "Simon {Janele}",
    year = "1999",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832416423",
    url = "https://m.diplom.de/document/217520"
}