@book { TheEconomicsofTwowayInterconnection,
    title = "The Economics of Two-way Interconnection",
    author = "Ulrich {Berger}",
    year = "2006",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b13999",
    url = "https://www.peterlang.com/document/1068532"
}