Elaborating a bit on mscharrer's point, I also added use diagnostics; and ran your script. This generated the following warning: 
Pseudo-hashes are deprecated at ...
    (D deprecated)  Pseudo-hashes were deprecated in Perl 5.8.0 and th
+ey
    will be removed in Perl 5.10.0, see perl58delta for more details.
    You can continue to use the fields pragma.

[download]

which pointed to your line: 

foreach my $key ( keys %{$library->{place}} )

[download]

I understand that this is not the root of your problem, but it does underscore the usefulness of the warnings/strict/diagnostics pragmas in helping you to debug your code. Of course, if you are using an older version of perl, you probably would not have seen this message.

In reply to Re: Problem traversing nested nodes XML::Simple by toolic
in thread Problem traversing nested nodes XML::Simple by quickskate

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