@book { WettbewerbinGegenwartvonNetzwerkeffekten,
    title = "Wettbewerb in Gegenwart von Netzwerkeffekten",
    author = "Michael {Dietrich}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1101652"
}