@book { EinfhrungvonProjektmanagement,
    title = "Einführung von Projektmanagement",
    author = "Marko {Kaiser}",
    year = "2009",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783640399567",
    url = "https://www.hausarbeiten.de/document/133287"
}