http://www.factmonster.com/ce6/society/A0837053.html
 

http://www.nebraskahistory.org/museum/teachers/material/
trail/indians/backgrnd.htm#anchor151753
 

http://www.gi.esu10.k12.ne.us/SDGI/Dodge.dragonweb/
Dodge.pages/NENativeStudy/Oto_main.html
 

http://www.trailsoftears.net/tribalinfo/content-otoemissouri.htm