M. Khattab, G.L. Gilmore, E.A. Sahovic, S.M. Miller, J.M. Rossetti, H. Abdulhaq, J. Lister. Viability And Potency Of Hematopoietic Progenitor Cells After Prolonged Cryopreservation At -80 °C. Biology of Blood and Marrow Transplantation. 2010 Feb 1; 16(2):s167.