“…Results regarding fragments of propositional logic that exhibit milder complexity for one of the two problems is also prevalent in the literature, e. g., in (Pretolani, 1996) it is analyzed how to extend tractable classes of SAT. In (Andrei et al, 2009) the complexity of both problems are studied when clauses are (not) related (literals appearing positive and negative in different clauses). Also the optimization problem, MaxSAT, has been studied in detail.…”