There are a TON of passages....also called Vietnam woman.."monkey faced"!!
Does the author, as a narrator, use the "monkey face" description or does a character in the book use that description?
Historical novels try to depict history as it actually was and a Vietnam veteran would write things that he heard and saw in Southeast Asia.
If an author writes about how things really were during the Vietnam War, some of his characters will use terms such as "gook" and other racial slurs. That is how things actually were.
If an author writes about how things really were in the Deep South during the 1950's or during the time the Huckleberry Finn character was supposed to have lived, you are sure to have the characters use the "N-Word".
This issue has come up before......"Should Huckleberry Finn be banned because it is racist for using the N-Word ?"..... and we conservatives have correctly called that Political Correctness since the novel was only being true to its era.