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2. Standard ideals;Grätzer;Magyar Tud. Akad. Mat. Fiz. Oszt. Közl,1959
3. Standard ideals in lattices;Grätzer;Acta Math. Acad. Sci. Hungar,1961
4. General Lattice Theory;Grätzer,2000
5. Theory of Symmetric Lattices;Maeda,1970