%0 Journal Article %T Spontaneous Transformation of Stem Cells In Vitro and the Issue of Cross-Contamination %A Anja Torsvik %A Gro V. R£¿sland %A Rolf Bjerkvig %J International Journal of Biological Sciences %D 2012 %I Ivyspring International Publisher %U http://www.biolsci.org/v08p1051.htm