Hrabe T, Chen Y, Pfeffer S, Kuhn Cuellar L, Mangold A, Förster F. PyTom: A python-based toolbox for localization of macromolecules in cryo-electron tomograms and subtomogram analysis. Journal of Structural Biology. 2012 May;178(2):177–88. doi: 10.1016/j.jsb.2011.12.003.