Could you explain how to apply <Use Encode> in my particular case? The relevant bit of program is like this

my $zip = Archive::Zip->new( $infile );
my $content = $zip->contents('content.xml');
my $workbook_ref = read_xml_string($content);
foreach my $sheet ( sort keys %$workbook_ref ) {
  foreach my $row( @{$$workbook_ref{$sheet}} ) {
    foreach my $cell_contents (@{$row}){
      next unless defined( $cell_contents );
      DECODE $cell_contents SOMEHOW
[download]

Thanks in advance
RichardH

P.S. For

      DECODE $cell_contents SOMEHOW
[download]

I tried this

  use Encode;
  my $octets = encode("iso-8859-1", $string);
  return( $octets );
[download]

Result of the above
Güldenstädt’s Redstart => Güldenstädt?s Redstart
i.e. "ü" for "ü" (good)
and "ä" for "ä" (good)
but "?" for "’" (Bad)
"’" is RIGHT SINGLE QUOTATION MARK, says charinfo(8217 )