A joint production of Mosfilm (USSR) and ICAIC (CUBA).
Originally released as a motion picture in 1964.
Screenplay, Yevgeny Yevtushenko, Enrique Pineda Barnet ; producer/director, Mikhail Kalatozov ; camera, Sergei Urusevsky ; music, Carlos Fariñas ; editor, N. Glagoleva.
Dialogue in Spanish and Russian, subtitles in English.