Fiction about indigenous / Native Americans

I have really enjoyed books by Caucasian authors Stan Jones about the Iñupiat, by Aimee and David Thurlo about the Navajo, by Tony and Anne Hillerman about the Navajo, William Kent Krueger about the Ojibwe of Minnesota, Margaret Coel about a metis Arapaho. When is it appropriation, when not?

Interesting posts:
Fine Print: 7 American Indian Women Novelists You Have to Read by Tanya H. Lee
1/15/14, http://indiancountrytodaymedianetwork.com/2014/01/15/fine-print-7-american-indian-women-novelists-worth-reading-153023
and
http://www.bachelorsdegreeonline.com/blog/2011/the-20-essential-american-indian-novels/
and
http://www.cynthialeitichsmith.com/lit_resources/diversity/native_am/nat_lit/native_lit_novels.html
and
Debbie Reese. American Indians in Children's Literature http://americanindiansinchildrensliterature.blogspot.com/


Carole laFavor about the Ojibwe. Linda Hogan. Susan Deer Cloud. Nicholas Black Elk.