package Schema::Document;
use base 'DBIx::Class::Core';
__PACKAGE__->table('tblDocument');
__PACKAGE__->add_columns(
    'id'          => { data_type=>'int', is_auto_increment=>1 },
    # Other cols.
);
__PACKAGE__->set_primary_key('id');
__PACKAGE__->has_many('document_authors', 'Schema::Document_Author', 'author');
__PACKAGE__->many_to_many( 'authors' => 'document_authors', 'author' );

package Schema::Author;
use base 'DBIx::Class::Core';
__PACKAGE__->table('tblAuthor');
__PACKAGE__->add_columns(
    'id'          => { data_type=>'int', is_auto_increment=>1 },
    # Other cols.
);
__PACKAGE__->set_primary_key('id');
__PACKAGE__->has_many('document_authors', 'Schema::Document_Author', 'document');
__PACKAGE__->many_to_many( 'documents' => 'document_authors', 'document' );

package Schema::Document_Author;
use base 'DBIx::Class::Core';
__PACKAGE__->table('tblDocument_Author');
__PACKAGE__->add_columns(
    'id'          => { data_type=>'int', is_auto_increment=>1 },
    'author_id'   => { data_type=>'int'                       }.
    'document_id' => { data_type=>'int'                       }.
);
__PACKAGE__->set_primary_key('id');
__PACKAGE__->belongs_to('document' => 'Schema::Document_Author');
__PACKAGE__->belongs_to('author'   => 'Schema::Document_Author');

##</code><code>##

my $authorsInYear_RS = $schema->resultset('Author')->search({
    'document.document_id' => { 'IN'  =>  $doc_ids->as_query()  },
},
{
    prefetch => { document_authors => 'document' }
});