@book { SocialMediaMarketingTwitterundAnsatzpunktedesMarketing,
    title = "Social Media Marketing. Twitter und Ansatzpunkte des Marketing ",
    author = "Aysun {Karge}",
    year = "2013",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783656457770",
    url = "https://www.hausarbeiten.de/document/229954"
}