The crystal structure of Ga-rich plumbogummite from Tsumeb, Namibia Mills, S. J. ; Kampf, A. R. ; Raudsepp, M. ; Christy, A. G. Abstract Publication: Mineralogical Magazine Pub Date: October 2009 DOI: 10.1180/minmag.2009.073.5.837 Bibcode: 2009MinM...73..837M