THE DESIGN CRITERIA OF “COMPOUND CROWN WHEEL” LONG-STROKE PUMPING UNIT
Cui Xuming, Tan Yun, Zhang Jianhui, Wang Dangfang, Huang Zhaozhi
Editorial office of ACTA PETROLEI SINICA . 1995, (1): 111 -117 .  DOI: 10.7623/syxb199501015