Pardo, Alfonso, Thierry Adatte, Gerta Keller, and Hedi Oberhänsli. (2024) 1999. “Paleoenvironmental Changes across the Cretaceous–Tertiary Boundary at Koshak, Kazakhstan, Based on Planktic Foraminifera and Clay Mineralogy”. Palaeogeography, Palaeoclimatology, Palaeoecology 154: 247–273. doi:10.1016/s0031-0182(99)00114-5.