@book { PortfolioalsBausteineinerneuenLernkultur,
    title = "Portfolio als Baustein einer neuen Lernkultur",
    author = "Carmen {Becker}",
    year = "2013",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-03564-3",
    url = "https://www.peterlang.com/document/1046516"
}