CHICAGO--(BUSINESS WIRE)--Today, the Bank of America Chicago Marathon announced 2012 champion Tsegaye Kebede of Ethiopia and current half marathon world record-holder Florence Kiplagat of Kenya will return to compete for the crown at the 38th annual event. Kebede and Kiplagat accent an international elite field that represents the global road to Rio de Janeiro. Many athletes hope to use the 2015 Chicago Marathon as a springboard (via qualifying times and notable performances) to representing th