There is a third string format in which you may see a reference (any reference!) presented: the string interpolation of a "raw" (i.e., un-dereferenced) reference variable. (In this example,  $blessed_ref has been bless-ed by default into the  main package.)

c:\@Work\Perl\monks>perl -wMstrict -le
"use Scalar::Util qw(reftype)
 ;;
 my $blessed_ref   = bless { 'foo' => 'bar' };
 my $unblessed_ref =       { 'bim' => 'bam' };
 ;;
 print 'ref: ',                   ref     $blessed_ref;
 print 'Scalar::Util::reftype: ', reftype $blessed_ref;
 ;;
 print qq{blessed stringization:   $blessed_ref};
 print qq{unblessed stringization: $unblessed_ref};
"
ref: main
Scalar::Util::reftype: HASH
blessed stringization:   main=HASH(0x1825f6c)
unblessed stringization: HASH(0x1826098)
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(In this example, I have used the  qq{text} form of the  "text" operator because Windoze uses  " (double-quote) as its command-line delimiter. See Quote and Quote-like Operators and Quote-Like Operators in perlop.)