2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/20137A comparison of microscopic theories of superconductivity in the limit of strong electron correlations is presented. We consider results for the two-dimensional t-J model obtained within the projection technique for the Green functions in terms of the Hubbard operators and the slave-fermion representation for the RVB state. It is argued that the latter approach resulting in the odd-symmetry p-wave pairing for fermions is inadequate.11 pages, RevTex, 1 figure, to appear in Condensed Matter Physics v.5, No.4 (2002)(Lviv, Ukraine) v.2: corrected typosStrongly Correlated Electronstext