Peng Lin Yingmin Jia Junping Du 0001 Fashan Yu Distributed leadless coordination for networks of second-order agents with time-delay on switching topology. 1564-1569 2008 ACC https://doi.org/10.1109/ACC.2008.4586714 conf/amcc/2008 db/conf/amcc/acc2008.html#LinJDY08