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3. W. F. Cole, H. Sorum, and W. H. Taylor, The Structures of the Plagioclase Feldspars, Acta Cryst. 4, 20 (1956).
4. P. Gay and W. H. Taylor, in The Structures of the Plagioclase Feldspars, IV. Variations in the Anorthite Structure, Acta Cryst. 6, 647 (1953).
5. V.N. Zyryanov, Phase Correspondence in the Systems of Alkaline Feldspars and Feldspathoids (Nauka, Moscow, 1981) [in Russian].