(United States)National safety council;by (United States)Donald E.Pienkos; (United States)National C;by (United States)Robert O'Neill; (United States)National Geographic Society;by (United States)Bill W.Tillery; (United States)Donald E.LaCourse;by (United States)Alfred E.Friedl; (United States)National C;by (United States)A.Barna; by (United States)Brian Tierney;by (United States)Donald H.Menzel; (United States)Educational Challenges,Inc.;by (United States)A.Manguel..et al; (United States)Elvio Angeloni;by (United States)Janet L.Hopson; (United States)Aminah B.R.;by (United States)Leonard B.; (United States)Glence div;by (United States)David M.Kroenke;