Original sentence: + Comparison of Union and CSARailroad mileage is from: Chauncey Depew (ed.The table shows the relative advantage of the Union over the Confederate States of America (CSA) at the start of the war.Union  CSA
Edited sentence: + Comparison of USA and CSARailroad mileage is from: Chauncey Depew (ed.The table shows the relative advantage of the USA over the Confederate States of America (CSA) at the start of the war.USA  CSA