8R L P Verley, T Sotberg,H Brennodden. Break-Out Soil Resistance for a Pipeline Partially Buried in Sand[A]. Proceedings of the 9OMAEConference[C], Houston,1990:121-125.
9D A Wanger, J D Murff, H Brennodden et al. Pipe-Soil Interaction Model,Proceedings of Nineteenth Annual Offshore Technology Conference[A]. Houston, Texas, paper OTC 5504[C], April, 1987 : 181-190.