[en] A review is given of experimental data on a study of correlation effects and properties of hadron jets produced in cumulative hadron-nucleus interactions for momenta of 10 and 40 GeV/s. The investigation has been performed on pictures from a 2 m propane bubble chamber of the high energy Laboratory, JINR. The established regularities show evidence for the existence in nuclei multiquark states which strongly differ from nucleons in their structure. Results of studying correlation phenomena and hadron jet production in cumulative hadron-nucleus processes indicate that the fragmentation of multiquark states in light nuclei is similar to that of quarks and diquarks in ''soft'' and ''hard'' hadron collisions. In hadron interactions with light nuclei the framentation of quarks into hadron jets occurs mainly outside the nucleus