2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/22528In strong-coupling superconductors with a short electron mean free path the self-energy effects in the superconducting order parameter play a major role in the phonon manifestation of the point-contact spectra at the above-gap energies. We derive asymptotic expressions of the phonon structure in MgB$%_{2}$ in the case $eV\ggΔ$ for tunnel, ballistic, and diffusive point-contacts and show that these expressions not only qualitatively, but also semi-quantitatively correspond to the measurements of the phonon structure in the point-contact spectra for the $π$-band of MgB$_{2}$ c-axis oriented thin films.4 pages, 4 figuresSuperconductivitytext