Jonek-Kowalska, Izabela; Turek, Marian - In: Equilibrium 6, Issue 2 (2011), pp. 91-107
Polish hard coal mining has been struggling with numerous problems for many years. Currently, the main challenge for the industry is the need to improve efficiency. It is the prerequisite for survival of mining industry. Considering the importance and topicality of the issue there are threats...
