Na<sub>1.85</sub>Mg<sub>1.85</sub>In<sub>1.15</sub>(PO<sub>4</sub>)<sub>3</sub> and Ag<sub>1.69</sub>Mg<sub>1.69</sub>In<sub>1.31</sub>(PO<sub>4</sub>)<sub>3</sub> with alluaudite-type structures
Acta crystallographica. Section E, Crystallographic communications