@book { StringsofNaturalLanguages,
    title = "Strings of Natural Languages",
    subtitle = "Unsupervised Analysis and Segmentation on the Expression Level",
    author = "Markus {Stengel}",
    year = "2007",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783836606271",
    url = "https://m.diplom.de/document/228992"
}