YANG, XB, ROACH, HI, CLARKE, NMP, HOWDLE, SM, SHAKESHEFF, KM and OREFFO, ROC, 2001. Induction of human osteoprogenitor chemotaxis, proliferation and differentiation by a novel bone factor, osteoblast stimulating factor-1 Journal of Bone and Mineral Research. 16(6), 1179-1179