2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/43698$c-\bar c$ correlations are calculated in the $k_t$-factorization approach. Different unintegrated gluon distributions (uGDF) from the literature are used. The results are compared with recent results of the FOCUS collaboration. The recently developed CCFM uGDF gives a good description of the data. Predictions for the HERA energies are presented.a talk at the international workshop DIS2004, Strbske Pleso, Slovakia, April 14-18, 5 pages, 3 figuresHigh Energy Physics - Phenomenologytext