see perldoc perlre. the s modifier is what you want... 
#!/usr/bin/perl

use strict;
use warnings;

my $a = join '', <DATA>;

my ( $b ) = $a =~ m{<a( .*? ) NGC:003288 }xms;

print $b;

__DATA__
<a id="GuidelineDataList__ctl1_doctitlelink" href="/summary/summary.as
+px?doc_id=4363">(1) Pertussis vaccination: use of acellular pertussis
+ vaccines among infants
and young children.
<br />(2) Use of diphtheria toxoid-tetanus toxoid-acellular pertussis 
+vaccine as a five-dose series. (Addendum)</a>
                    Centers for Disease Control and Prevention - Feder
+al Government Agency [U.S.].
                                        1997 Mar 28 (revised 2000 Nov;
+ addendum released 2003 Sep 26)
                                        .
                                                            25 pages.

        NGC:003288

[download]

In reply to Re: help match this by lima1
in thread help match this by Anonymous Monk

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