“…There have been proposed many formalism within approach II; the operator formalism developed by Batalin and Fradkin [4,5,10], the projection operator formalism [11,12,13,14,15,16], the algebraic approach proposed by Ohnuki and Kitakado [17] and the first-order singular Lagrangian formalism proposed by Faddeev and Jackiw [18,19]. Using the projection operator method [11,12] (POM), then, we have shown that the operator-algebra in the approach II contain the quantum corrections caused by the noncommutativity in the re-ordering of constraint-operators in the products of operators, which can never be obatined by the approach I. Alternative formalism of quantization is the Wely-Wigner-Moyal (WWM) quantization [20,21], and has been investigated for the constraint systems [22,23,24,25].…”