Zubkova N V , Kolitsch U , Pekov I V , Turchkova A G , Vigasina M F , Pushcharovsky D Y , Tillmanns E , European Journal of Mineralogy , 21 (2009) p.495-506, Crystal chemistry of Rb-, Sr-, Ba-, Ca- and Pb-exchanged forms of natural hilairite, Locality: Kirovskii mine, Khibiny alkaline complex, Kola Peninsula, Russia, Note: sample was synthesized by cation exchange at 150 C