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http://www.usatf.org/Events---Calendar/2014/World-Half-Marathon-Championships/Athlete-Info/Selection-Procedures.aspx
Team Size: 5 per gender
Selection Procedures
Three (3) positions will be selected from among the top-10 finishers at the 2014 USA Half Marathon Championships
The remaining two (2) positions will be selected based on half marathon performances list(s).
Consideration for selection to the men’s and women’s teams will be given to athletes who finished in the top ten in the 2013 USA 20 km Championships or 2013 USA 12 km Championships providing (a) that performance is sub 1:04:00 (men) or 1:14:30 (women), for a half marathon, or equivalent per the Mercier Scoring Tables, and (b) the athletes demonstrates fitness between January 1, 2014 and March 1, 2014.