Дмитриев, Д.А., Савко, А.Д., Куролап, С.А., Калаев, В.Н. and Иванов, Д.А. 2018. Mineral-raw material base of non-metallic mineral resources of central black earth region and its rational use. Article 2. the model of rational using of mineral-raw material base of non-metals. Proceedings of Voronezh State University. Series: Geology. 4 (Oct. 2018), 39-56. DOI:https://doi.org/10.17308/geology.2018.4/1646.