def references(name):
    """Provides references for the DMSP instruments and experiments

    Parameters
    ----------
    name : str
        Instrument name

    Returns
    -------
    refs : str
        String providing reference guidenance for the DMSP data

    """

    refs = {'ivm': ' '.join(('F. J. Rich, Users Guide for the Topside',
                             'Ionospheric Plasma Monitor (SSIES, SSIES-2 and',
                             'SSIES-3) on Spacecraft of the Defense',
                             'Meteorological Satellite Program (Air Force',
                             'Phillips Laboratory, Hanscom AFB, MA, 1994),',
                             'Vol. 1, p. 25.'))}

    return refs[name]