... 

my $ele = $tree->look_down(_tag=> 'div',id=>'right');
       $ele->delete_content();
    
    my $i=0;
    
    while ($i < $right_panel) {
#element friendly node
        $ele->push_content(['strong'], "$matrix_title[$i]",['p'],"$matrix_summary[$i]",['br'],['br'],['a', {href=>"art.cgi?art=$matrix_id[$i]"}, "Read on ... ", ],['br'],['hr'],['br']);
                
    $i++;
    
    }
...

print $cgi->header(); 
print $tree->as_HTML();


##</code><code>##


\n -> [br] 
<p> -> [p]
[link = permonks.org] - >  ['a', {href=>"perlonks.org"}]

##</code><code>##

... 

while ($i < $right_panel) {
     
    $matrix_summary[$i]=~s/\n/<br>/g;
     
    #my $htm_elem = qq(['strong'], "$matrix_title[$i]",['p'],"$matrix_summary[$i]",['br'],['br'],['a', {href=>"art.cgi?art=$matrix_id[$i]"}, "Read on ... ", ],['br'],['hr'],['br']);
    my $li=HTML::Element->new('~literal','text', qq(<strong> $matrix_title[$i]</strong><p>$matrix_summary[$i]</p><br><a href="art.cgi?art=$matrix_id[$i]">Read on ...</a><br><hr><br>)
                              
                              );
        
        $ele->push_content($li);        
    $i++;
    
    }