Four American explorers have made a combined contribution of inestimable worth, in regard to modern pterosaurs: Garth Guessman, Paul Nation, David Woetzel, and Jonathan Whitcomb. It seems that to have just one of them taken away from the history of this research would been extremely detrimental. Each has contributed unique and essential elements.
Paul Nation has gone on four expedition in Papua New Guinea; Garth Guessman has gone on two; David Woetzel and Jonathan Whitcomb, one each. But Woetzel and Whitcomb have written extensively, giving us countless web pages and two scientific papers in the Creation Research Society Quarterly.
Other explorers could be mentioned: Jacob Kepas, James Blume, and others. Kepas and Blume, in particular, have helped enormously, with interpreting on expeditions in Papua New Guinea and doing their own searching for modern pterosaurs. Both of them have had their own sightings, with Kepas getting two good views of giant flying creatures.
That being said, Guessman, Nation, Woetzel, and Whitcomb have contributed much in bringing this subject to the attention of Americans.