Bartlomiej Liana, Bartosz Papiernik (2017). NATURAL AND DRILLING INDUCED FACTORS INFLUENCING THE BRITTLENESS ESTIMATION BASED ON SONIC LOGS. SGEM International Multidisciplinary Scientific GeoConference EXPO Proceedings; 17th International Multidisciplinary Scientific GeoConference SGEM2017, Science and Technologies in Geology, Exploration and Mining, 741-748. https://doi.org/10.5593/sgem2017/14/s06.093