$Href = {1=>1, 2=>2};
*H = $Href;   # aliases the referenced variable as a real variable
print $H{1};

##</code><code>##

use strict;
sub foo {
      my $Href = shift;
      my (%H);
      *H = $Href;   # define the alais  
      print $H{1};
}

##</code><code>##

use strict;
our %H;   #  have to create the global or local complains
sub foo {
      my $Href = shift;
      local (%H);  # instead of my use local
      *H = $Href;   # define the alias  
      print $H{1};
}