$html = '
	<p>text</p>
	<a href="/about1/">about 1</a>
	<p>text</p>
	<p>text</p>
	<a rel="noindex,nofollow" href="/about2/">nofollow 1</a>
	<a rel="nofollow" href="/about3/">nofollow 2</a>
	<a href="/about4/" rel="nofollow">nofollow 3</a>
	<a href="/about5/" rel="noindex,nofollow">nofollow 4</a>
	<p>text</p>
	<a href="/about6/">about 2</a>
	<p>text</p>
';
preg_match_all( '#<.*?href=["|\'|](.*?)["|\'|].*?>#uims', $html, $tmp );
print_r($tmp[1]);
die();

$html = '
	<p>text</p>
	<a href="/about1/">about 1</a>
	<p>text</p>
	<p>text</p>
	<a rel="noindex,nofollow" href="/about2/">nofollow 1</a>
	<a rel="nofollow" href="/about3/">nofollow 2</a>
	<a href="/about4/" rel="nofollow">nofollow 3</a>
	<a href="/about5/" rel="noindex,nofollow">nofollow 4</a>
	<p>text</p>
	<a href="/about6/">about 2</a>
	<a href="/about7/" rel=noindex,nofollow>nofollow 5</a>
	<a href="/about8/" rel=noindex>nofollow 6</a>
	<p>text</p>
';
preg_match_all( '#<.*?href=["\'](.*?)["\'].*?>#uims', $html, $tmp );
print_r($tmp[1]);
die();