3[1]Kudo S,Ono M,Russell WJ.Ossification of thoracic ligamenta flava.AJR Am J Roentgenol,1983,141:117-121
4[4]Hirabayashi K,Miyakawa J,Satomi K,et al.Operative results and postoperative progression of ossification among patients with ossification of cervical posterior longitudinal ligament.Spine,1981,6:354-364