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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In World War II, Navajo Marines linked troops in the Pacific war using their language. The 'code' was never broken. Here is the official story. Daniel can tailor your tour to your needs. Reservations are recommended.