@book { FiveLeadershipTheoriesAppliedinBarackObamasFirst100DaysasPresident,
    title = "Five Leadership Theories Applied in Barack Obama's First 100 Days as President",
    author = "Eric  {Coggins}",
    year = "2009",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783640364497",
    url = "https://www.hausarbeiten.de/document/130531"
}