Jean-Michel Fourneau Leïla Kloul Fabrice Valois Performance modelling of hierarchical cellular networks using PEPA. 83-99 2002 50 Perform. Eval. 2/3 db/journals/pe/pe50.html#FourneauKV02 http://dx.doi.org/10.1016/S0166-5316(02)00101-3