Thermochemical investigations of natural phosphate with ammonium sulphate additivePetkova, Vilma; Pelovski, Y.; Dombalov, I.; Tõnsuaadu, KaiaJournal of thermal analysis and calorimetry2005 / p. 701-708 Thermochemical investigations of natural phosphate with ammonium sulphate additivePetchova, V.; Pelovski, Y.; Dombalov, I.; Tõnsuaadu, KaiaICTAC 13 : 13th International Congress on Thermal Analysis and Calorimetry : XXVI Conference AICAT-GICAT : Chia Laguna, September 12-19, 2004 : book of abstracts2004 / p. P2-105A