:: deftheorem defines times-additive QUANTAL1:def 7 :
for IT being non empty QuantaleStr holds
( IT is times-additive iff for a, b, c being Element of IT holds
( (a "\/" b) [*] c = (a [*] c) "\/" (b [*] c) & c [*] (a "\/" b) = (c [*] a) "\/" (c [*] b) ) );