Yunqing Xu Yanxun Chang Gennian Ge Hantao Zhang Frame self-orthogonal Mendelsohn triple systems of type h<sup>n</sup>. 5049-5063 2008 308 Discrete Mathematics 22 http://dx.doi.org/10.1016/j.disc.2007.09.002 db/journals/dm/dm308.html#XuCGZ08