  The application of k_t - factorization supplemented with the CCFM small-x
evolution equation to heavy quark production is discussed. The b-b_bar
production cross sections at the TEVATRON can be consistently described using
the k_t-factorization formalism together with the unintegrated gluon density
obtained within the CCFM evolution approach from a fit to HERA F_2 data.
Special attention is drawn to the comparison with measured visible cross
sections. The visible measured cross sections at HERA are compared to the
hadron level Monte Carlo generator CASCADE.
