1) Albright F, Smith PH, Richardson AM: Postmenopausal osteoporosis, its clinical features. JAMA 116: 2465-2474, 1941.
2) Goldsmith NF, Johnston JO, Picetti G, Garcia C: Bone mineral in the radius and vertebral osteoporosis in an insured population. A correlative study using 125-I photon absorption and miniature roentgenography. J Bone Joint Surg 55: 1276-1293, 1973.
4) Cameron JR, Mazess RB, Sorenson JA: Precision and accuracy of bone mineral determination by direct photon absorptiometry. Invest Radiol 3: 141-150, 1968.