Correct use of Blockquote, q and cite?

The blockquote element (also the q element) can optionally have a cite attribute to specify a URI where the quote came from. HTML5 says user agents should make that link available to the user, and HTML4 doesn’t say anything at all. I would include the URI both in the cite attribute and as an inline link, since browsers don’t handle it.

More Thoughts About Blockquotes than are Strictly Required

So, we went looking for a semantic element to wrap this pattern in, and for a few reasons, we arrived at figure:

<span class="token tag"><span class="token punctuation"><</span>figure <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>quote<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
     <span class="token tag"><span class="token punctuation"><</span>blockquote<span class="token punctuation">></span></span>It is the unofficial force—the Baker Street irregulars.<span class="token tag"><span class="token punctuation"></</span>blockquote<span class="token punctuation">></span></span>
     <span class="token tag"><span class="token punctuation"><</span>figcaption<span class="token punctuation">></span></span>Sherlock Holmes, <span class="token tag"><span class="token punctuation"><</span>cite<span class="token punctuation">></span></span>Sign of Four<span class="token tag"><span class="token punctuation"></</span>cite<span class="token punctuation">></span></span><span class="token tag"><span class="token punctuation"></</span>figcaption<span class="token punctuation">></span></span>
<span class="token tag"><span class="token punctuation"></</span>figure<span class="token punctuation">></span></span>