<?php
                    $date_modified_timestamp_max = 0;
                    foreach ( $results as $result ) {
                        $date_modified_timestamp = strtotime( $result['date_modified'] );
                        if ( $date_modified_timestamp > $date_modified_timestamp_max ) {
                            $date_modified_timestamp_max = $date_modified_timestamp;
                        }
                    }
                    if ( $date_modified_timestamp_max ) {
                        LastModified( $date_modified_timestamp_max );
                    }