Native American Graves Protection and

Extraction from ancient remains is a completely destructive process and, as such, this process might not be permitted, for example, on extremely rare samples. Likewise, in the United States, Native American human remains that are to be repatriated to their descendants (Native American Graves Protection and Repatriation Act, or NAGPRA) may be unavailable for study. 

Table 9.3 Major stipulations of the Native American Graves Protection and Repatriation Act (NAGPRA) of 1990 ...

Native American Graves Protection and Repatriation Act (NAGPRA)... 

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