1. BP plc (2010) BP statistical review of world energy 2010
2. Brown ET, Hoek E (1978) Technical note trends in relationships between measured in situ stress and depth. Int J Rock Mech Min Sci Geomech Abstr 15(4):211–215
3. Cheng YP, Yu QX (2003) Application of safe and high-efficient exploitation system of coal and gas in coal seams. J China Univ Mining Technol 32(5):471–475
4. Cheng YP, Fu JH, Yu QX (2009) Development of gas extraction technology in coal mines of China. J Min Saf Eng 26:127–139
5. Cheng YP, Wang HF, Wang L, Zhou HX, Liu HY, Liu HB, Wu DM, Li W (2010) Theories and engineering applications on coal mine gas control. China University of Mining and Technology Press, Xuzhou