Another resource that helps with various ethnic types, and that I think was done in a very respectful manner, are these tutorials by majnouna over at deviantART. Here you learn how to properly draw people of various ethnic and racial groups, as well as about many of these groups' most ancient standards of beauty and other cultural tidbits.
http://majnouna.deviantart.com/art/Guide-to-Human-Types-part-1-32046017
http://majnouna.deviantart.com/art/Guide-to-Human-Types-part-2-33220929
http://majnouna.deviantart.com/art/Guide-to-Human-Types-part-3-34877428
This really helped me correct a lot of problems I had in accurately reflecting people the way I wanted to in portrait drawings. It also made me able to spot where people are from very easily.
http://majnouna.deviantart.com/art/Guide-to-Human-Types-part-1-32046017
http://majnouna.deviantart.com/art/Guide-to-Human-Types-part-2-33220929
http://majnouna.deviantart.com/art/Guide-to-Human-Types-part-3-34877428
This really helped me correct a lot of problems I had in accurately reflecting people the way I wanted to in portrait drawings. It also made me able to spot where people are from very easily.