2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/184666We use the chain of simple heuristic expedients to obtain perturbative and exactly solvable relativistic spectra for a family of two-fermionic bound systems with Coulomb-like interaction. In the case of electromagnetic interaction the spectrum coincides up to the second order in a coupling constant with that following from the quantum electrodynamics. Discrepancy occurs only for S-states which is the well-known difficulty in the bound-state problem. The confinement interaction is considered too. PACS number(s): 03.65.Pm, 03.65.Ge, 12.39.Pn16 pages, LaTeX 2.09Nuclear TheoryHeuristic Models of Two-Fermion Relativistic Systems with Field-Type Interactiontext