diff --git a/SeedDMS_Core/Core/inc.ClassDocument.php b/SeedDMS_Core/Core/inc.ClassDocument.php
index cbf26d2ab..96b2355c7 100644
--- a/SeedDMS_Core/Core/inc.ClassDocument.php
+++ b/SeedDMS_Core/Core/inc.ClassDocument.php
@@ -1813,7 +1813,7 @@ class SeedDMS_Core_Document extends SeedDMS_Core_Object { /* {{{ */
 		$status = $version->getStatus();
 		$stID = $status["statusID"];
 
-		$queryStr = "DELETE FROM `tblDocumentContent` WHERE `document` = " . $this->getID() .	" AND `version` = " . $version->_version;
+		$queryStr = "DELETE FROM `tblDocumentContent` WHERE `document` = " . $this->getID() .	" AND `version` = " . $version->getVersion();
 		if (!$db->getResult($queryStr)) {
 			$db->rollbackTransaction();
 			return false;
@@ -1831,7 +1831,7 @@ class SeedDMS_Core_Document extends SeedDMS_Core_Object { /* {{{ */
 			return false;
 		}
 
-		$queryStr = "DELETE FROM `tblDocumentStatus` WHERE `documentID` = '". $this->getID() ."' AND `version` = '" . $version->_version."'";
+		$queryStr = "DELETE FROM `tblDocumentStatus` WHERE `documentID` = '". $this->getID() ."' AND `version` = '" . $version->getVersion()."'";
 		if (!$db->getResult($queryStr)) {
 			$db->rollbackTransaction();
 			return false;
@@ -1861,7 +1861,7 @@ class SeedDMS_Core_Document extends SeedDMS_Core_Object { /* {{{ */
 				return false;
 			}
 		}
-		$queryStr = "DELETE FROM `tblDocumentReviewers` WHERE `documentID` = '". $this->getID() ."' AND `version` = '" . $version->_version."'";
+		$queryStr = "DELETE FROM `tblDocumentReviewers` WHERE `documentID` = '". $this->getID() ."' AND `version` = '" . $version->getVersion()."'";
 		if (!$db->getResult($queryStr)) {
 			$db->rollbackTransaction();
 			return false;
@@ -1890,26 +1890,26 @@ class SeedDMS_Core_Document extends SeedDMS_Core_Object { /* {{{ */
 				return false;
 			}
 		}
-		$queryStr = "DELETE FROM `tblDocumentApprovers` WHERE `documentID` = '". $this->getID() ."' AND `version` = '" . $version->_version."'";
+		$queryStr = "DELETE FROM `tblDocumentApprovers` WHERE `documentID` = '". $this->getID() ."' AND `version` = '" . $version->getVersion()."'";
 		if (!$db->getResult($queryStr)) {
 			$db->rollbackTransaction();
 			return false;
 		}
 
-		$queryStr = "DELETE FROM `tblWorkflowDocumentContent` WHERE `document` = '". $this->getID() ."' AND `version` = '" . $version->_version."'";
+		$queryStr = "DELETE FROM `tblWorkflowDocumentContent` WHERE `document` = '". $this->getID() ."' AND `version` = '" . $version->getVersion()."'";
 		if (!$db->getResult($queryStr)) {
 			$db->rollbackTransaction();
 			return false;
 		}
 
-		$queryStr = "DELETE FROM `tblWorkflowLog` WHERE `document` = '". $this->getID() ."' AND `version` = '" . $version->_version."'";
+		$queryStr = "DELETE FROM `tblWorkflowLog` WHERE `document` = '". $this->getID() ."' AND `version` = '" . $version->getVersion()."'";
 		if (!$db->getResult($queryStr)) {
 			$db->rollbackTransaction();
 			return false;
 		}
 
 		// remove document files attached to version
-		$res = $this->getDocumentFiles($version->_version);
+		$res = $this->getDocumentFiles($version->getVersion());
 		if (is_bool($res) && !$res) {
 			$db->rollbackTransaction();
 			return false;