Individual #Niobrara_River__Niobrara  a tributary of the Missouri River
  instance of:  river
  part of:  USA__United_States_of_America__United_States__America__US__U.S.__U.S.A.  North American republic containing 50 states - 48 conterminous states in North America plus Alaska in northwest North America and the Hawaiian Islands in the Pacific Ocean; achieved independence in 1776
     part of:  North_America  a continent (the third largest) in the western hemisphere connected to South America by the Isthmus of Panama
        part of:  northern_hemisphere  the hemisphere north of the equator
        part of:  western_hemisphere__westernhemisphere__occident__New_World  the hemisphere that includes North and South America
        part of:  the_Americas__America  North and South America

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