1. J. R. Boles, “Composition, Optical Properties, Cell Dimensions and Thermal Stability of Some Heulandite Group Zeolites,” Am. Mineral. 57, 1463–1493 (1972).
2. A. Alietti, “Polymorphism and Crystal Chemistry of Heulandites and Clinoptilolites,” Am. Mineral. 57, 1448–1462 (1970).
3. B. Mason and L. B. Sand, “Clinoptilolite from Patagonia. The Relationships between Clinoptilolite and Heulandite,” Am. Mineral. 45, 341–350 (1960).
4. F. A. Mumton, “Clinoptilolite Redefined,” Am. Mineral. 45, 351–359 (1960).
5. A. Alietti, G. Gottardi, and L. Poppi, “The Heat Behavior of Cation Exchanged Zeolites with Heulandite Structure,” Tschermarks Min. Pet. Mitt. 21, 291–298 (1972).