A paper on the effect of the ANT 13 locus on malting quality and agronomic performance was published in 1995.
Bregitzer, P., Wesenberg, D.M., and Jones, B.L. 1995. Effect of the ANT-13 locus (proanthocyanidin-free) on the malting quality and agronomic performance of barley. J. Am. Soc. Brew. Chem. 53 (4):191-193.