Foundations of Physics, vol.23, no.5, pp.837-840, 1993 (SCI-Expanded)
A brief review of two-body Dirac and Kemmer-Duffin-Petiau approaches for the bound state problem of two fermions is presented from an algebraic point of view in a comparative manner. Reduction of the direct product of two Dirac spaces is discussed. © 1993 Plenum Publishing Corporation.