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Hello everyone, I have three comments wrt m-newmat.tex, version 2000.11.16: I had to change a \startypen into \starttypen to get a typeset version. At the end of the file, Hans was looking for applications of subarrays: $$\sum_{\startsubarray[c] 1\leq i \leq 10\crcr 1\leq j \leq i \stopsubarray} i^j = 11567154195$$ (Actually, I think \\ should work in place of \crcr, too.) The definition of substack looks broken to me: first of all, there is no \simplestartsubstack and secondly the command should not be named \start... since there is no corresponding \stop... command. Suggested code: \def\substack {\startsubarray[c]#1\stopsubarray} (Since the argument will be typeset anyway, I think it should be given in {}, right?) Usage: $$\sum_{\substack{1\leq i \leq 10\crcr 1\leq j \leq i} i^j = 11567154195$$ regards, Christopher Creutzig