New naturally occurring phases of secondary origin from Jáchymov (Joachimsthal) - Ondruš, Petr; Veselovský, František; Skála, Roman; Cisařová; Hloušek, Jan; Frýda, Jiří; Vavřín, Ivan; Čejka, Jiří; Gabašová, Ananda (Journal of the Czech Geological Society, 1997)