冀西北后坊子石墨矿地质特征及矿床成因
张兴康, 樊玉朋, 靳松, 贾正海

Geological characteristics and ore genesis of Houfangzi graphite deposit in Northwestern Hebei Province
ZHANG Xingkang, FAN Yupeng, JIN Song, JIA Zhenghai
后坊子石墨矿矿石照片