1. RonHochstetler and BarryE. Prentice, An X-Prize forTransport Airships, June 3 - 6, 2007, CTRF 42nd Annual Conference; "North AmericanTransportationNetworks: Gapsand Opportunities" conference, Winnipeg, Manitoba,
2. Richard G. Newell and NathanE. Wilson, June 2005, Technology PrizesforClimate Change Mitigation, RFF DP 05-33,Resources for the Future