Strangways, William T. H. F. (1 January 1822). "I.—An Outline of the Geology of Russia". Transactions of the Geological Society of London. S2-1 (1): 1–39. doi:10.1144/transgslb.1.1.1. ISSN2042-5295. S2CID140667355.
Strangways, William T. H. F. (1 January 1822). "I.—An Outline of the Geology of Russia". Transactions of the Geological Society of London. S2-1 (1): 1–39. doi:10.1144/transgslb.1.1.1. ISSN2042-5295. S2CID140667355.
Strangways, William T. H. F. (1 January 1822). "I.—An Outline of the Geology of Russia". Transactions of the Geological Society of London. S2-1 (1): 1–39. doi:10.1144/transgslb.1.1.1. ISSN2042-5295. S2CID140667355.