2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/41710We demonstrate that the explicit mass dependence of the exponent in the power--like energy behavior of the vector--meson production cross-section in the processes of virtual photon interactions with a proton gamma^*p --> Vp obtained in the off--shell extension of the approach based on unitarity is in a quantitative agreement with the high--energy HERA experimental data.7 pages, 4 figuresHigh Energy Physics - Phenomenologytext