2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/147468The new form of the composite operator generalizing the Cooper pairs for a BCS superconductor is introduced. The approach is similar to the derivation of the composite operator of the odd - frequency superconductors. The examples of the $d_{x^2-y^2}-,~d_{xy}-$ and $p-$ wave composite operators for a 2D $t-J$ model are given.revtex, corrected version - minor changesCondensed Mattertext