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Art: Hal Foster and John Cullen Murphy (from page 2172, September 24, 1978). At this point in Prince Valiant's run, John Cullen Murphy, who had been quietly assisting Hal Foster since 1970, was well into his first decade of drawing the strip over Foster's writing and roughs.
Source: Prince Valiant (Vol. 49): Road to Sorrow's End, comprising pages 2168 (August 27, 1978) through 2211 (June 24, 1979). Fantagraphics Books, 2003.