<p>These are all equivalent:</p> <blockquote> <blockquote> <p>nested blockquote</p> </blockquote> </blockquote> <blockquote> <blockquote> <p>nested blockquote</p> </blockquote> </blockquote> <blockquote> <blockquote> <p>nested blockquote</p> </blockquote> </blockquote> <blockquote> <blockquote> <p>nested blockquote</p> </blockquote> </blockquote> <p>This is not:</p> <blockquote> <p>nested</p> <blockquote> <p>blockquote</p> </blockquote> </blockquote>