“…The gradient search and Boltzmann search heuristics have been first proposed in [16], and the super-peer election thresholds have been introduced in [43]. However, compared with [44], [16] and [43], the algorithms presented in this paper have been substantially elaborated and improved. In particular, the neighbour selection algorithm has been extended, the push-based aggregation algorithm has been replaced by a push-pull algorithm, a new super-peer election approach based on system load and adaptive thresholds has been introduced, an approach to multiple utility functions support has been added, a bootstrap mechanism has been described, and most importantly, a substantially more elaborate evaluation has been performed.…”