Jean-Charles Faugère & Ludovic Perret An efficient algorithm for decomposing multivariate polynomials and its applications to cryptography, Journal of Symbolic Computation Volume 44 Issue 12, December, 2009 Pages 1676-1689 generalizes the Kozen-Landau decomposition algorithm to multivariate polynomials (or so it claims). I took a brief look at the original Kozen-Landau JSC paper and it seems very good. Oddly enough, Landau is now a professor of "social policy" which is not the subject you might have expected. I saw her testifying to congress about the FBI/Apple case, I thought she was doing great; but unfortunately far as I know nothing she did affected the US government's brain-dead conceptions about crypto & the law. -- Warren D. Smith http://RangeVoting.org <-- add your endorsement (by clicking "endorse" as 1st step)