Fangmin Xu Chao Qiu Andong Guo Chenglin Zhao Access control for software-defined heterogeneous wireless access network. 520-524 2016 ISCIT https://doi.org/10.1109/ISCIT.2016.7751686 conf/iscit/2016 db/conf/iscit/iscit2016.html#XuQGZ16