TY JOUR TI THE ESSENCE, SIGNIFICANCE AND CLASSIFICATION OF (PRELIMINARY) RESEARCH AS A NON-PROCEDURAL FORM OF USING SPECIAL KNOWLEDGE KW preliminary research KW specialist's research KW specialist's conclusion KW forms of using special knowledge KW specialist KW non-procedural form. JO Forensics: yesterday, today, tomorrow AU Ryzhkov, I.V. AU Ryzhkova, A.A. PY 2024 IS 0 PB East Siberian institute of the Ministry of Internal Affairs of the Russian Federation