Tor Helleseth Alexander Kholosha Geir Jarle Ness Characterization of m-Sequences of Lengths 2<sup>2k</sup>-1 and 2<sup>k</sup>-1 With Three-Valued Cross Correlation. 2236-2245 2007 53 IEEE Transactions on Information Theory 6 http://dx.doi.org/10.1109/TIT.2007.896881 db/journals/tit/tit53.html#HellesethKN07