use strict; use warnings;
my $VAR1 = [
   {
     'name' => 'Discount',
     'reference' => '100       ',
     'type' => 'Paper'
   },
   {
     'name' => 'Documents',
     'reference' => '100       ',
     'type' => 'Paper'
   },
   {
     'name' => 'Money',
     'reference' => '340       ',
     'type' => 'Plastic'
   },
   {
     'name' => 'State',
     'reference' => '40        ',
     'type' => 'Cotton'
   },
   {
     'name' => 'Slice',
     'reference' => '30        ',
     'type' => 'Cotton'
   },   {
     'name' => 'Part',
     'reference' => '45        ',
     'type' => 'Cotton'
   },
];

my %results;
$results{$_->{type}}{$_->{name}} += $_->{reference} for (@{$VAR1});

print "Results:\n";
for my $type (keys %results) {
  print "\t$type:\n";
  for my $name (keys %{$results{$type}} ) {
    print "\t\t$name - ".$results{$type}{$name}."\n";
  }
}
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