Depth sorting alpha blended objects
http://blogs.msdn.com/b/shawnhar/archive/2009/02/18/depth-sorting-alpha-blended-objects.aspx

SpriteBatch and renderstates in XNA Game Studio 4.0
http://blogs.msdn.com/b/shawnhar/archive/2010/06/18/spritebatch-and-renderstates-in-xna-game-studio-4-0.aspx

XNA 4.0에서의 SaveStateMode 구현하기
http://gomdong-alchemist.tistory.com/entry/XNA-40%EC%97%90%EC%84%9C%EC%9D%98-SaveStateMode-%EA%B5%AC%ED%98%84%ED%95%98%EA%B8%B0