TY JOUR TI About the systematic approach in criminal law KW system KW element KW system approach KW system-structural analysis KW external (functional) connections KW hierarchical (vertical) type KW mutual influence KW criminal law JO Vestnik of the St. Petersburg University of the Ministry of Internal Affairs of Russia AU Nikolaev, K.D. PY 2021 IS 2021 PB SAINT-PETERSBURG UNIVERSITY OF THE MINISTRY OF INTERNAL AFFAIRS OF THE RUSSIAN FEDERATION