Citation: Mazzi, F.; Munno, R. (1983). Calciobetafite (new mineral of the pyrochlore group) and related minerals from Campi Flegrei, Italy; crystal structures of polymignyte and zirkelite: comparison with pyrochlore and zirconolite Note: B(2,3) for Ti61 has been changed to satisfy symmetry constraints. American Mineralogist, 68, pp. 262-276.