@misc{misc4c20debe,
title   = {Discontinuous local semiflows for Kurzweil equations leading to Lasalle's invariance principle for differential systems with impulses at variable times},
author = {Afonso, S and Bonotto, Everaldo de Mello and Federson, Marcia and Schwabik, S},
year = {2010},
publisher = {ICMC-USP}
}