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Gupta, S.L.; Soni, R.N., Spectroscopic Determination of the Thermodynamic Ionization Consant of 3,5-Dinitrosalicylic Acid in Aqueous Medium from 11 deg to 60 deg and Related Thermodynamic Functions, J. Inst. Chem. (India), 1968, 40, 154-9. [all data]