Kravkov S. Soil life due to its origin and properties. In Russian/Kravkov S. Zhizn pochvy v svyazi s ee proiskhozhdeniem i svoystvami. Petrograd Naturalists Library: A.S. Panafidina, 1919, 39 p. Please contact us for details on condition of available copies of the book. SKUalbce50defcc1419bd4.