Ying Zhang Shashidhar Gandham Qingfeng Huang Distributed Minimal Time Convergecast Scheduling for Small or Sparse Data Sources. 301-310 2007 RTSS http://doi.ieeecomputersociety.org/10.1109/RTSS.2007.19 conf/rtss/2007 db/conf/rtss/rtss2007.html#ZhangGH07