Stephan Recker Multilayered Wholesale Resource Trading to Foster Service Diversity in Packet-Switching Networks. 181-205 2004 27 Telecommunication Systems 2-4 http://springerlink.metapress.com/index/10.1023/B:TELS.0000041008.16406.5a db/journals/telsys/telsys27.html#Recker04