Whang Peter G, Wang Jeffrey C
Department of Orthopaedic Surgery, University of California, Los Angeles School of Medicine, 10833 LeConte Avenue, 76-124CHS, Box 956902, Los Angeles, CA 90095-6902, USA.
Spine J. 2003 Mar-Apr;3(2):155-65. doi: 10.1016/s1529-9430(02)00539-9.