Obruchev V. A., Prof. Ore Deposits: Part descriptive. In Russian (ask us if in doubt)/Obruchev V. A., prof. Rudnye mestorozhdeniya: Chast opisatelnaya. M.-L.: State Publishing House, 1st Model Printing House, 1929. XXIV, 562, 2c. SKUalb2b2ab2ebe0bbd1b0.