1. Determining rock strength with specimens of irregular shape;Protodyakonov;Ugol,1957
2. New methods of determining mechanical properties of rocks;Protodyakonov,1960
3. Determining the strength of rock strata on irregularly-shaped specimens;Ilivitskii;Ugol,1961
4. The compressive strength of coal;Evans;Colliery Engng,1961
5. The compressive strength of coal;Evans;Colliery Engng,1961