# Bellow, you have two dereference # The arrow dereferences the HashRef $VAR1 # The @{ } dereferences the ArrayRef under 'book' => foreach my $book ( @{ $VAR1->{'book'} } ) { # Then, each $book is another HashRef print $book->{'isbn'}, "\n"; print $book->{'title'}, "\n"; # But 'author' is an ArrayRef: foreach my $author ( @{ $book->{'author'} } ) { print "Author: ", $author, "\n"; } }