@book { GeologypetrographyandpetrogenesisofpegmatitefromGwonGwonNigeria,
    title = "Geology, petrography and petrogenesis of pegmatite from Gwon-Gwon, Nigeria",
    author = "Abdullahi {Adamu Mohammed} and A.I. {Haruna} and A.M. {Usman}",
    year = "2016",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    url = "https://www.hausarbeiten.de/document/321506"
}