You will also have permission to reprint the document after updates, so long as you destroy the original. This article was written in reference to the second largest tribe in Arizona. Advice given is valid here as well. One of the contributors is Navajo. Makes for informative reading.
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Features include the Treaty of 1868, Navajo Flag, articles on Navajo history, access to regional newspapers, university archives and research libraries. Historical collections, legal documents and newsletters are available. Web sites have entries for the Dineh and most other tribes. The 'code' was never broken. Here is the official story.