遇层角法在瓦斯抽采定向钻孔中的计算与应用
徐保龙,魏宏超,金新,等
The Calculation and Application of the Angle of Penetration Method in Coal Gas Exploiting Directional Borehole
煤炭工程 . 2013, (9): 91 -93 .  DOI: 10.11799/ce201309031