Masaaki Harada Akihiro Munemasa Some restrictions on weight enumerators of singly even self-dual codes. 1266-1269 2006 52 IEEE Transactions on Information Theory 3 http://doi.ieeecomputersociety.org/10.1109/TIT.2005.864416 db/journals/tit/tit52.html#HaradaM06