@article{Powell2004,
    author = "Powell, A.V. and Vaqueiro, P. and Knight, K.S. and Chapon, L.C. and Sanchez, R.D.",
    title = "Structure and magnetism in synthetic pyrrhotite Fe7 S8: a powder neutron-diffraction study",
    journal = "Physical Review, Serie 3. B - Condensed Matter (18,1978-)",
    year = "2004",
    volume = "70",
    pages = "014415-1-014415-12",
    ASTM_id = "PRBMDO"
}

@article{Tokonami1972,
    author = "Tokonami, M. and Nishiguchi, K. and Morimoto, N.",
    title = "Crystal structure of a monoclinic pyrrhotite (Fe7 S8)",
    journal = "American Mineralogist",
    year = "1972",
    volume = "57",
    pages = "1066-1080",
    ASTM_id = "AMMIAY"
}