Perry BC, Zhou D, Wu X, Yang FC, Byers MA, Chu G, Hockema JJ, Woods EJ, Goebel WS. Collection, Cryopreservation, and Characterization of Human Dental Pulp–Derived Mesenchymal Stem Cells for Banking and Clinical Use. Tissue Engineering Part C: Methods. June 2008, 14(2): 149-156. doi:10.1089/ten.tec.2008.0031.