diff --git a/org.adempiere.base/src/org/adempiere/util/ModelClassGenerator.java b/org.adempiere.base/src/org/adempiere/util/ModelClassGenerator.java
index a5e0a29e5b..60ce8359fa 100644
--- a/org.adempiere.base/src/org/adempiere/util/ModelClassGenerator.java
+++ b/org.adempiere.base/src/org/adempiere/util/ModelClassGenerator.java
@@ -19,6 +19,8 @@
  *****************************************************************************/
 package org.adempiere.util;
 
+import static org.compiere.model.SystemIDs.REFERENCE_PAYMENTRULE;
+
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.OutputStreamWriter;
@@ -35,7 +37,6 @@ import java.util.logging.Level;
 
 import org.adempiere.exceptions.DBException;
 import org.compiere.Adempiere;
-import org.compiere.model.MPaymentLookup;
 import org.compiere.util.CLogger;
 import org.compiere.util.DB;
 import org.compiere.util.DisplayType;
@@ -429,7 +430,7 @@ public class ModelClassGenerator
 		//	Payment Validation
 		if (displayType == DisplayType.Payment)
 		{
-			String staticVar = addListValidation (sb, MPaymentLookup.PAYMENTRULE_AD_Reference_ID, columnName);
+			String staticVar = addListValidation (sb, REFERENCE_PAYMENTRULE, columnName);
 			sb.insert(0, staticVar);			
 		}
 
diff --git a/org.adempiere.base/src/org/compiere/model/MPaymentLookup.java b/org.adempiere.base/src/org/compiere/model/MPaymentLookup.java
index e696a4aaca..1aad341ce0 100644
--- a/org.adempiere.base/src/org/compiere/model/MPaymentLookup.java
+++ b/org.adempiere.base/src/org/compiere/model/MPaymentLookup.java
@@ -13,6 +13,8 @@
  *****************************************************************************/
 package org.compiere.model;
 
+import static org.compiere.model.SystemIDs.REFERENCE_PAYMENTRULE;
+
 import java.io.Serializable;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
@@ -38,8 +40,6 @@ public class MPaymentLookup extends Lookup implements Serializable {
 	 * 
 	 */
 	private static final long serialVersionUID = -6863672221350217533L;
-
-	public static final int PAYMENTRULE_AD_Reference_ID = 195;
 	
 	/**	Context					*/
 	private Properties 		m_ctx;
@@ -136,7 +136,7 @@ public class MPaymentLookup extends Lookup implements Serializable {
 		try
 		{
 			pstmt = DB.prepareStatement(sb.toString(), null);
-			pstmt.setInt(1, PAYMENTRULE_AD_Reference_ID);
+			pstmt.setInt(1, REFERENCE_PAYMENTRULE);
 			if (!isBaseLanguage)
 				pstmt.setString(2, ad_language);
 			rs = pstmt.executeQuery();
diff --git a/org.adempiere.base/src/org/compiere/model/SystemIDs.java b/org.adempiere.base/src/org/compiere/model/SystemIDs.java
index a225d2b4fd..e72eee1bc8 100644
--- a/org.adempiere.base/src/org/compiere/model/SystemIDs.java
+++ b/org.adempiere.base/src/org/compiere/model/SystemIDs.java
@@ -112,10 +112,11 @@ public class SystemIDs
 	public final static int REFERENCE_DATATYPE_URL = 40;
 	public final static int REFERENCE_DATATYPE_YES_NO = 20;
 
-	public static final int REFERENCE_AD_USER = 110;
+	public final static int REFERENCE_AD_USER = 110;
 	public final static int REFERENCE_DOCUMENTACTION = 135;
 	public final static int REFERENCE_PAYMENTRULE = 195;
 	public final static int REFERENCE_POSTING_TYPE = 125;
+	public final static int REFERENCE_POSTED = 234;
 	public final static int REFERENCE_YESNO = 319;
 	public final static int REFERENCE_WIZARDSTATUS = 200003;
 
@@ -134,7 +135,7 @@ public class SystemIDs
 	public final static int USER_SYSTEM = 0;
 
 	public final static int WINDOW_ACCOUNTCOMBINATION = 153;
-	public static final int WINDOW_CUSTOMERRETURN = 53097;
+	public final static int WINDOW_CUSTOMERRETURN = 53097;
 	public final static int WINDOW_INVENTORYMOVE = 170;
 	public final static int WINDOW_LOT = 257;
 	public final static int WINDOW_MATERIALRECEIPT = 184;
@@ -144,7 +145,7 @@ public class SystemIDs
 	public final static int WINDOW_PRINTFORMAT = 240;
 	public final static int WINDOW_PRODUCTION = 191;
 	public final static int WINDOW_REQUESTS_ALL = 232;
-	public static final int WINDOW_RETURNTOVENDOR = 53098;
+	public final static int WINDOW_RETURNTOVENDOR = 53098;
 	public final static int WINDOW_SHIPMENT_CUSTOMER = 169;
 	public final static int WINDOW_WAREHOUSE_LOCATOR = 139;
 	public final static int WINDOW_WINDOW_TAB_FIELD = 102;	
diff --git a/org.adempiere.ui.swing/src/org/compiere/grid/ed/VButton.java b/org.adempiere.ui.swing/src/org/compiere/grid/ed/VButton.java
index 60eebae0ca..2d0698e655 100644
--- a/org.adempiere.ui.swing/src/org/compiere/grid/ed/VButton.java
+++ b/org.adempiere.ui.swing/src/org/compiere/grid/ed/VButton.java
@@ -16,6 +16,10 @@
  *****************************************************************************/
 package org.compiere.grid.ed;
 
+import static org.compiere.model.SystemIDs.REFERENCE_DOCUMENTACTION;
+import static org.compiere.model.SystemIDs.REFERENCE_PAYMENTRULE;
+import static org.compiere.model.SystemIDs.REFERENCE_POSTED;
+
 import java.awt.Color;
 import java.awt.event.ActionListener;
 import java.beans.PropertyChangeEvent;
@@ -88,13 +92,13 @@ public final class VButton extends CButton
 		//	Special Buttons
 		if (columnName.equals("PaymentRule"))
 		{
-			readReference(195);
+			readReference(REFERENCE_PAYMENTRULE);
 			this.setForeground(Color.blue);
 			setIcon(Env.getImageIcon("Payment16.gif"));    //  29*14
 		}
 		else if (columnName.equals("DocAction"))
 		{
-			readReference(135);
+			readReference(REFERENCE_DOCUMENTACTION);
 			this.setForeground(Color.blue);
 			setIcon(Env.getImageIcon("Process16.gif"));    //  16*16
 		}
@@ -109,7 +113,7 @@ public final class VButton extends CButton
 		}
 		else if (columnName.equals("Posted"))
 		{
-			readReference(234);
+			readReference(REFERENCE_POSTED);
 			this.setForeground(Color.magenta);
 			setIcon(Env.getImageIcon("InfoAccount16.gif"));    //  16*16
 		}
diff --git a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/editor/WButtonEditor.java b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/editor/WButtonEditor.java
index f618aa079a..0ea7fe495a 100644
--- a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/editor/WButtonEditor.java
+++ b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/editor/WButtonEditor.java
@@ -17,6 +17,10 @@
 
 package org.adempiere.webui.editor;
 
+import static org.compiere.model.SystemIDs.REFERENCE_DOCUMENTACTION;
+import static org.compiere.model.SystemIDs.REFERENCE_PAYMENTRULE;
+import static org.compiere.model.SystemIDs.REFERENCE_POSTED;
+
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
@@ -111,12 +115,12 @@ public class WButtonEditor extends WEditor implements IProcessButton
         String columnName = super.getColumnName();
         if (columnName.equals("PaymentRule"))
         {
-            readReference(195);
+            readReference(REFERENCE_PAYMENTRULE);
             getComponent().setImage("/images/Payment16.png");    //  29*14
         }
         else if (columnName.equals("DocAction"))
         {
-            readReference(135);
+            readReference(REFERENCE_DOCUMENTACTION);
             getComponent().setImage("/images/Process16.png");    //  16*16
         }
         else if (columnName.equals("CreateFrom"))
@@ -130,7 +134,7 @@ public class WButtonEditor extends WEditor implements IProcessButton
         }
         else if (columnName.equals("Posted"))
         {
-            readReference(234);
+            readReference(REFERENCE_POSTED);
             getComponent().setImage("/images/InfoAccount16.png");    //  16*16
         }