5Lubinskin A, Blenkarn K A.Buckling of tubing in pumping wells, its effects and means for controlling it.Trans. of ASME,1975:210~225
6Mitchell R F.New concepts for helical buckling.SPEDE, 1988:303~310
7Cheatham J B,Jr.and Pattillo P D.Helical postbuckling configuration of a weightless column under the action of an axial load.Society of Petroleum Engineers Journal,1984:467~472