a WGBH production in association with the British Broadcasting Corporation for NOVA ; produced & directed by Carl Charlson ; written by David McCullough
a NOVA production by the WGBH/Boston Science Unit in association with BBC-TV, NDR International Hamburg and Nederlandse Omroepprogramma Stichting ; written, produced and directed by Linda Garmon
written, produced and directed by Larry Engel & Thomas Lucas ; executive producer, Paula S. Apsell ; a Nova production by Cineworks Inc. in association with WGBH/Boston and BBC TV
a Nova production by Green Umbrella Ltd. for WGBH Boston in association with BBC-TV, NDR International, Hamburg and Wild Media ; written and directed by Nick Upton ; producers, Peter Jones and Nick Upton
written, produced and directed by Linda Garmon ; a Nova production by the WGBH/Boston Science Unit in association with BBC-TV, NDR International Hamburg and Nederlandse Omroepprogramma Stichting