Reuven Bar-Yehuda Magnús M. Halldórsson Joseph Naor Hadas Shachnai Irina Shapira Scheduling Split Intervals. 1-15 2006 36 SIAM J. Comput. 1 http://dx.doi.org/10.1137/S0097539703437843 db/journals/siamcomp/siamcomp36.html#Bar-YehudaHNSS06