Drivage development and support of roadways and faces in deep mines - 750 metres and over - and consequently in more difficult mining, geological and atmospheric conditions / transmitted by the Government of Poland.
1981
Полное описание
Условное обозначение[E/ECE/]COAL/GE.4/R.19/Add.1
ЗаглавиеDrivage development and support of roadways and faces in deep mines - 750 metres and over - and consequently in more difficult mining, geological and atmospheric conditions / transmitted by the Government of Poland.
АвторыPoland
ДатаGeneva : UN, 6 Nov. 1981.
Описание
17 p. : tables