《汉书·传·匈奴传上》
现在中原人虽然假装不娶自己父兄的妻子，亲属却逐渐疏远，以至于互相杀戮，以至于改姓改族，都是由这一类的事情引起的。
今中国虽阳不取其父兄之妻，亲属益疏则相杀，至到易姓，皆从此类也。
People in Central Plains pretend not to marry their own father's or brother's wives, but relatives gradually grow estranged, killing each other or changing their surnames or clans, all caused by this sort of thing.