00774nam0-22002771i-450-99000356032040332120001010000356032FED01000356032(Aleph)000356032FED0100035603220000920d1962----km-y0itay50------baitay-------001yyGrain yields and the American food supplyD. G. JohnsonR. L. GustafsonLondons.e.1962Johnson,David Gale72182Gustafson R.l.ITUNINARICAUNIMARCBK990003560320403321SE 055.01.04-036419DECSEDECSEGrain yields and the American food supply493108UNINAING01