When you download your file, the email address in question is hidden in html, so you first need to strip the html. I use lynx below, but there are Perl modules. Once you have the text, split into lines, just test each line.

This dosn't account for emails that somehow get newlines in them, like thru bad cut and pasting, and the regex may leave something to be desired.

The script below prints out 2 addresses in the array, select the first array element

OUTPUT: careers@flatironssolutions hr@flatironssolutions
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#!/usr/bin/perl
use warnings;
use strict;

my $html= $ARGV[0];
my $content = `lynx --dump $html`;
#print "$content\n";

my @lines = split(/\n/,$content);
#print "@lines\n";

my @addrs;

while(<@lines>){

  if( my ($num)= $_ =~ /(\b\w{1,}\Q@\E\w{1,}\b)/ ){
      #print "$num \n";
      push @addrs, $num;
     }
  }

print "@addrs\n";
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