Karayigit, A., Sutcu, E., Temel, A. & Gundogdu, M. (2022) Vertical variations of minerals in clayey sedimentary rocks in the cores of two-deep exploration wells from the Kozlu coalfield (Zonguldak, NW Turkiye), with emphasis on tonstein (schieferton) formation. TURKISH JOURNAL OF EARTH SCIENCES , 31(6), 597-621.