Individual #Niagara_River__Niagara  a river flowing from Lake Erie into Lake Ontario; forms boundary between Ontario and New York
  instance of:  #river
  part of:  #Canada  #USA
  part:  #Niagara__Niagara_Falls  waterfall in Canada is the Horseshoe Falls; in the United States it is the American Falls
     part:  #American_Falls  a part of Niagara Falls in western New York (north of Buffalo)
     part:  #Canadian_Falls__Horseshoe_Falls  a part of Niagara Falls in Ontario

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