@book { FriendshipunderStress,
    title = "Friendship under Stress",
    subtitle = "U.S.-Swiss Relations 1900-1950",
    author = " {Anonym}",
    year = "1971",
    publisher = "Peter Lang Verlag",
    address = "Lausanne, Switzerland",
    url = "https://www.peterlang.com/document/1069354"
}