The code for the paper:
Chen, T. L., Hsieh, D. N., Hung, H., Tu, I. P., Wu, P. S., Wu, Y. M., Chang, W. H., and Huang, S. Y. (2014). gamma-SUP: a clustering algorithm for cryo-electron microscopy images of asymmetric particles. The Annals of Applied Statistics, 8, 259-285.