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Earlier we have introduced a definition of strong equal-ity of classical tautologies, according to which two tautologies areequal iff they have the same hardness. The strong equality im-plies well known equality, but not vice versa. The strong equalityis based on the notion of determinitive conjunct, using of whichsome new deduction system for classical propositional logic weredefined. Here the notions of strong equality of tautologies for var-ious logics are suggested and the idea of construction of universaldeduction system for various propositional logics is given.