[en] The ABBN-93 299-group cross-section library is used as a source of neutron data for criticality calculations with the MMK-KENO Monte Carlo criticality code. Validation of criticality calculations is performed using the data presented in the 'International Handbook of Evaluated Criticality Safety Benchmark Experiments'. This paper contains a description of a validation method based on statistical analysis of discrepancies between calculated and benchmark-model k_eff's and the results of this validation for different types of experiments. Another validation method using a well-known procedure of group cross-section adjustment based on the maximum likelihood method (generalized least-squares method) and results of the validation for water-moderated highly enriched uranium homogeneous critical systems using selected experiments of the HEU-SOL-THERM type are also presented