Composition not stated
P-dbR-3c (No. 167)
conditions not stated; default record
Volk & Wöhlecke 2009 p. 2 prints R3m without a reference (conflict); the CIF value is kept.
Boysen & Altorfer, Acta Crystallographica Section B 50 405 (1994), COD 2101175-2101185 high-temperature entries