NOW IT WORKS, I must have fat-fingered the previous 300 times. Please disregard.
Esteemed (and steamy) monks, I'm trying to dereference a hash to build a link. I've run a query and am looping thru an array of arrays to build a table. On the third column I want to insert the link - using the contents of that column @$_[1] to derefernce the value from the hash $real_hash->{@$_[0]}, but I get no data. I'm wondering if behind the scenes I'm overwriting some built-in variable. Thanks in advance for your help. Code follows --------------- 
sub makeTable {
    my ($ref, $cols) = @_;
    my $one_col = ""; 
    
    #pull in ref. to hash (doc. name, URL)
    my $links_ref =  ($cols =~ /MPS/) ? &getMPSlinks : "";     

    #----make column titles, and begin html code for table
    my @cols = split (/,/,$cols);        
    foreach (@cols)
        {$labels .= qq|<td>$_</td>|;}
    my $table = qq|<table class="center"><tr class="table_labels">$lab
+els</tr>|;
  

    foreach (@$ref) { #loop thru array of arrays, inside we'll take ea
+ch array and break out into table
       $table .= ++$count % 2 == 1 ? qq|<tr class="row_light">| : qq|<
+tr class="row_dark">|; #alaternate row colors          
       #---Build tables here------------------------------------------
+-----

       if ($form{"query"} eq "deptcodes") {           
            my $doc_num = qq|@$_[2]|;
            #PROBLEM CHILD ON NEXT LINE
            $table .=  qq|<td>@$_[0]</td><td>@$_[1]</td><td><a href="$
+links_ref->{@$_[0]}" target="_blank">@$_[2]</a></td>|;               
+   
       }    
    }
    $table .= "</table>";
    return($table);
}

#this returns a ref to a hash.   key is doc. name,  value is URL
 sub getMPSlinks {
        our %mps_hash=();
        my ($one_mps, $one_url) = "";
        open(HANDLE, "< $cgi_path/mpslinks.txt")  or die "***Couldn't 
+open $path for reading: $!\n";
        while (<HANDLE>) 
            {
                ($one_mps, $one_url) = split (/\|/,$_);
                $mps_hash{$one_mps} = "$one_url";
                #print "<strong>$one_mps</strong><br> $one_url";
            }
        close (HANDLE);
        return (\%mps_hash);      
 }

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In reply to trouble dereferencing a hash reference by hipnoodle

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