The Carboniferous-Permian boundary in the USSR. (In: The Carboniferous of the USSR. 8th International Congress of Carboniferous Stratigraphy and Geology. R.H.Wagner et al, editors)
Reference:
Rauser-Chernousova,D.M. et al. (1979)
The Carboniferous-Permian boundary in the USSR. (In: The Carboniferous of the USSR. 8th International Congress of Carboniferous Stratigraphy and Geology. R.H.Wagner et al, editors) Yorkshire Geological Society Occasional Publication
Vol. 4 P. 175- 195