Aina Johansen Tor Helleseth Xiaohu Tang The Correlation Distribution of Quaternary Sequences of Period 2(2<sup>n-1)</sup>. 3130-3139 2008 54 IEEE Transactions on Information Theory 7 http://dx.doi.org/10.1109/TIT.2008.924727 db/journals/tit/tit54.html#JohansenHT08