J. P. Briggs, Simon J. Pennycook, J. R. Fergusson, J. Jäykkä, E. P. S. Shellard. Separable projection integrals for higher-order correlators of the cosmic microwave sky: Acceleration by factors exceeding 100. J. Comput. Physics, 310:285-300, 2016. [doi]
Abstract is missing.