@book { Smalltalk,
    title = "Smalltalk",
    subtitle = "Die große Kunst des kleinen Gesprächs",
    author = "Doris {Märtin}",
    year = "2012",
    publisher = "dotbooks Verlag",
    address = "München, Deutschland",
    doi = "10.3239/9783943835670",
    url = "https://www.dotbooks.de/document/199223"
}