1. Laboratory for Mineralized Tissue Research; Hospital for Special Surgery; 535 East 70th Street New York 10021 New York
2. Cleveland Clinic Lerner College of Medicine; Cleveland Clinic; 9500 Euclid Avenue Cleveland 44195 Ohio
3. Department for Clinical and Experimental Medicine; Linkoping University; SE-581 83 Linkoping Sweden
4. Sibley School of Mechanical and Aerospace Engineering; Cornell University; Ithaca 14853 New York