http://pec.lib.wvu.edu/record/P177661943The Use of first records versus the average of all records in dam-daughter comparisons when proving sires.Journal article reprint from: <em>Journal of Dairy Science</em>, v.26:no.10 (1943:Oct.).Putnam, Dexter Nevins, 1916-Conklin, C. T.Bowling, G. A. (George Augustus), 1902-Dairy cattle--Breeding.14256