2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/128487It is shown that the visibility of multi-photon interference for classical sources grows rapidly with the order of interference. For three-photon and four-photon interference of two coherent sources, the visibility can be as high as 81.9% and 94.4%, respectively, - much higher than the 'classical limit' of two-photon interference (50%). High-visibility three-photon and four-photon interference has been observed in experiment, for both coherent and pseudo-thermal light.4 pages, 5 figuresQuantum Physicstext