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Sherryl R. Bisgrove, Michael T. Simonich, Nadine M. Smith, Airlie Sattler, Roger W. Innes, A Disease Resistance Gene in Arabidopsis with Specificity for Two Different Pathogen Avirulence Genes, The Plant Cell, Vol. 6, No. 7 (Jul., 1994), pp. 927-933
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Bisgrove et al. (1994) studied this question.
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