As a part of our long collaboration with Professor J. E. Johnson (The Scripps Research Institute, La Jolla, CA) we have written software that may be of general interest and which we would be glad to distribute. In particular, there are packages as described in the following:

- Software to compute basis functions for icosahedrally-symmetric subspaces of the spaces spanned by spherical harmonics of degree
*l*for any*l*. The theory is described in the papers by Yibin Zheng in*Acta Crystallographica*and*SIAM Journal on Mathematical Analysis*. The software is written in Mathematica. We can also provide tables of coefficients for the linear transformation from spherical harmonics to the new basis functions. - Software to compute 3-D reconstructions of particles from single-particle cryo electron microscopy. This is very much a work in progress. The current theory is described in the paper by Yili Zheng and Qiu Wang in
*Journal of the Optical Society of America*and the paper by Nan Xu in*IEEE Transactions on Image Processing.*The current software is in Matlab.