1971 Watkins Glen 6 hours.
Watkins Glen, New York State, USA. 24th July 1971. Rd 11.
Mark Donohue/David Hobbs (Ferrari 512M), retired, leads Jo Siffert/Gijs van Lennep (Porsche 917K), 2nd position, at the start, action.
World Copyright: LAT Photographic.
Ref: Colour Transparency.