D.Zh. Kalimanova, A.D. Kalimukasheva, J.A. Kubasheva, & A.A. Nazhetova. (2019). FEATURES OF HYDROCHEMICAL AND GEOCHEMICAL INDICATORS OF THE NORTH-EASTERN PART OF THE CASPIAN SEA (ZONES, OIL AND GAS FIELDS OF THE KAZAKHSTAN SECTOR). Известия НАН РК. Серия химии и технологии, (1), 27–31. извлечено от http://89.250.84.46/chemistry-technology/article/view/1257