diff --git a/AlgebraicDataflowArchitectureModel/src/generators/CodeGeneratorFromDataFlowGraph.java b/AlgebraicDataflowArchitectureModel/src/generators/CodeGeneratorFromDataFlowGraph.java
index 39de6cd..ea45a55 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/CodeGeneratorFromDataFlowGraph.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/CodeGeneratorFromDataFlowGraph.java
@@ -937,9 +937,26 @@
 								v++;
 							}
 						}
-						for (Variable var: message.getVariables().values()) {
-							resInputParams.add(langSpec.newVariableDeclaration(var.getType(), var.getName()));
-							mainInputParams.add(langSpec.newVariableDeclaration(var.getType(), var.getName()));
+						for (Map.Entry<Position, Variable> varEnt: message.getVariables().entrySet()) {
+							Variable var = varEnt.getValue();
+							String refVarName = null;
+							for (ChannelMember refCm: ((DataTransferChannel) ch).getReferenceChannelMembers()) {
+								Expression varExp = refCm.getStateTransition().getMessageExpression().getSubTerm(varEnt.getKey());
+								if (varExp != null && varExp instanceof Variable) {
+									if (refCm.getStateTransition().getCurStateExpression().contains(varExp)) {
+										refVarName = refCm.getResource().getResourceName();
+										break;
+									}
+								}
+							}
+							if (refVarName != null) {
+								// var has come from a reference resource.
+								resInputParams.add(langSpec.newVariableDeclaration(var.getType(), refVarName));
+							} else {
+								// var has not come from a reference resource.
+								resInputParams.add(langSpec.newVariableDeclaration(var.getType(), var.getName()));
+								mainInputParams.add(langSpec.newVariableDeclaration(var.getType(), var.getName()));
+							}
 						}
 						input = langSpec.newMethodDeclaration(((Term) message).getSymbol().getImplName(), false, null, resInputParams);
 						if (component != null) {
@@ -1028,6 +1045,18 @@
 					
 					// Add an invocation to the accessor method.
 					if (inputAccessor != null) {
+						for (ChannelMember rc: ((DataTransferChannel) ch).getReferenceChannelMembers()) {
+							// For each reference channel member, get the current state of the reference side resource by pull data transfer.
+							ResourcePath ref = rc.getResource();
+							if (!out.getResource().equals(ref)) {
+								String refVarName = ref.getResourceName();
+								Expression refGetter = JavaCodeGenerator.pullAccessor.getDirectStateAccessorFor(ref, null);
+								String[] sideEffects = new String[] {""};
+								String refExp = refGetter.toImplementation(sideEffects);
+								String refTypeName = ref.getResourceStateType().getInterfaceTypeName();
+								inputAccessor.addFirstStatement(sideEffects[0] + refTypeName + " " + refVarName + " = " + refExp + ";");
+							}
+						}
 						Expression resExp = getPullAccessor().getDirectStateAccessorFor(out.getResource(), null);
 						List<String> args = new ArrayList<>();
 						if (resExp instanceof Term) {
@@ -1039,8 +1068,20 @@
 						}
 						String resourceAccess = resExp.toImplementation(new String[] {null});
 						if (message instanceof Term) {
-							for (Variable var: message.getVariables().values()) {
-								args.add(var.getName());
+							for (Map.Entry<Position, Variable> varEnt: message.getVariables().entrySet()) {
+								String refVarName = null;
+								for (ChannelMember rc: ((DataTransferChannel) ch).getReferenceChannelMembers()) {
+									Expression varExp = rc.getStateTransition().getMessageExpression().getSubTerm(varEnt.getKey());
+									if (varExp != null && rc.getStateTransition().getCurStateExpression().contains(varExp)) {
+										refVarName = rc.getResource().getResourceName();
+										break;
+									}
+								}
+								if (refVarName != null) {
+									args.add(refVarName);
+								} else {
+									args.add(varEnt.getValue().getName());									
+								}
 							}
 						}
 						inputAccessor.addStatement(langSpec.getMethodInvocation(resourceAccess, input.getName(), args) + langSpec.getStatementDelimiter());
@@ -1049,7 +1090,7 @@
 					if (input != null) {
 						// Add a statement to update the state field to the input method.
 						try {
-							Expression updateExp = ((DataTransferChannel) ch).deriveUpdateExpressionOf(out, getPullAccessor());
+							Expression updateExp = ((DataTransferChannel) ch).deriveUpdateExpressionOf(out, getRefAccessor());
 							// Replace Json constructor with a constructor of the child resource.
 							ResourceHierarchy outRes = out.getResource().getResourceHierarchy();
 							if (outRes.getChildren().size() == 1 && outRes.getChildren().iterator().next().getNumParameters() > 0) {
diff --git a/AlgebraicDataflowArchitectureModel/src/generators/JavaCodeGenerator.java b/AlgebraicDataflowArchitectureModel/src/generators/JavaCodeGenerator.java
index b15569b..76971ed 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/JavaCodeGenerator.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/JavaCodeGenerator.java
@@ -23,6 +23,7 @@
 import models.algebra.Expression;
 import models.algebra.Field;
 import models.algebra.Parameter;
+import models.algebra.Position;
 import models.algebra.Symbol;
 import models.algebra.Term;
 import models.algebra.Type;
@@ -610,9 +611,26 @@
 									v++;
 								}
 							}
-							for (Variable var: message.getVariables().values()) {
-								resInputParams.add(new VariableDeclaration(var.getType(), var.getName()));
-								mainInputParams.add(new VariableDeclaration(var.getType(), var.getName()));
+							for (Map.Entry<Position, Variable> varEnt: message.getVariables().entrySet()) {
+								Variable var = varEnt.getValue();
+								String refVarName = null;
+								for (ChannelMember refCm: ((DataTransferChannel) ch).getReferenceChannelMembers()) {
+									Expression varExp = refCm.getStateTransition().getMessageExpression().getSubTerm(varEnt.getKey());
+									if (varExp != null && varExp instanceof Variable) {
+										if (refCm.getStateTransition().getCurStateExpression().contains(varExp)) {
+											refVarName = refCm.getResource().getResourceName();
+											break;
+										}
+									}
+								}
+								if (refVarName != null) {
+									// var has come from a reference resource.
+									resInputParams.add(new VariableDeclaration(var.getType(), refVarName));
+								} else {
+									// var has not come from a reference resource.
+									resInputParams.add(new VariableDeclaration(var.getType(), var.getName()));
+									mainInputParams.add(new VariableDeclaration(var.getType(), var.getName()));
+								}
 							}
 							MethodDeclaration input = new MethodDeclaration(
 															((Term) cm.getStateTransition().getMessageExpression()).getSymbol().getImplName(),
diff --git a/AlgebraicDataflowArchitectureModel/src/generators/JavaMethodBodyGenerator.java b/AlgebraicDataflowArchitectureModel/src/generators/JavaMethodBodyGenerator.java
index 083520a..443d7bf 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/JavaMethodBodyGenerator.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/JavaMethodBodyGenerator.java
@@ -509,7 +509,7 @@
 						}
 						if (input != null) {
 							// In each resource
-							Expression updateExp = entry.getKey().deriveUpdateExpressionOf(out, JavaCodeGenerator.pushAccessor);
+							Expression updateExp = entry.getKey().deriveUpdateExpressionOf(out, JavaCodeGenerator.refAccessor);
 							// Replace Json constructor with a constructor of the child resource.
 							ResourceHierarchy outRes = out.getResource().getResourceHierarchy();
 							if (outRes.getChildren().size() == 1 && outRes.getChildren().iterator().next().getNumParameters() > 0) {
@@ -569,6 +569,26 @@
 							if (mainComponent != null) {
 								MethodDeclaration inputAccessor = getMethod(mainComponent, input.getName());
 								if (inputAccessor != null) {
+									Set<ResourcePath> referredSet = referredResources.get(input);
+									for (ChannelMember rc: entry.getKey().getReferenceChannelMembers()) {
+										// For each reference channel member, get the current state of the reference side resource by pull data transfer.
+										ResourcePath ref = rc.getResource();
+										if (referredSet == null) {
+											referredSet = new HashSet<>();
+											referredResources.put(input, referredSet);
+										}
+										if (!out.getResource().equals(ref)) {
+											String refVarName = ref.getResourceName();
+											if (!referredSet.contains(ref)) {
+												referredSet.add(ref);
+												Expression refGetter = JavaCodeGenerator.pullAccessor.getDirectStateAccessorFor(ref, null);
+												sideEffects = new String[] {""};
+												String refExp = refGetter.toImplementation(sideEffects);
+												String refTypeName = ref.getResourceStateType().getInterfaceTypeName();
+												inputAccessor.addFirstStatement(sideEffects[0] + refTypeName + " " + refVarName + " = " + refExp + ";");
+											}
+										}
+									}
 									Expression resExp = JavaCodeGenerator.pullAccessor.getDirectStateAccessorFor(out.getResource(), null);
 									String args = "";
 									String delimiter = "";
@@ -583,8 +603,20 @@
 									String resourceAccess = resExp.toImplementation(new String[] {null});
 									if (out.getStateTransition().getMessageExpression() instanceof Term) {
 										Term message = (Term) out.getStateTransition().getMessageExpression();
-										for (Variable var: message.getVariables().values()) {
-											args += delimiter + var.getName();
+										for (Map.Entry<Position, Variable> varEnt: message.getVariables().entrySet()) {
+											String refVarName = null;
+											for (ChannelMember rc: entry.getKey().getReferenceChannelMembers()) {
+												Expression varExp = rc.getStateTransition().getMessageExpression().getSubTerm(varEnt.getKey());
+												if (varExp != null && rc.getStateTransition().getCurStateExpression().contains(varExp)) {
+													refVarName = rc.getResource().getResourceName();
+													break;
+												}
+											}
+											if (refVarName != null) {
+												args += delimiter + refVarName;
+											} else {
+												args += delimiter + varEnt.getValue().getName();
+											}
 											delimiter = ", ";
 										}
 									}
diff --git a/AlgebraicDataflowArchitectureModel/src/generators/JerseyCodeGenerator.java b/AlgebraicDataflowArchitectureModel/src/generators/JerseyCodeGenerator.java
index 7e81d3b..b791f97 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/JerseyCodeGenerator.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/JerseyCodeGenerator.java
@@ -23,6 +23,7 @@
 import models.algebra.Expression;
 import models.algebra.Field;
 import models.algebra.Parameter;
+import models.algebra.Position;
 import models.algebra.Symbol;
 import models.algebra.Term;
 import models.algebra.Type;
@@ -535,13 +536,31 @@
 							} else {
 								resourcePath = "\"" + resourcePath + "\"";
 							}
-							for (Variable var: message.getVariables().values()) {
-								String paramName = var.getName();
-								VariableDeclaration param = new VariableDeclaration(var.getType(), paramName);
-								resInputParams.add(param);
-								param = new VariableDeclaration(var.getType(), paramName);
-								param.addAnnotation(new Annotation("FormParam", "\"" + paramName + "\""));
-								rootInputParams.add(param);
+							for (Map.Entry<Position, Variable> varEnt: message.getVariables().entrySet()) {
+								Variable var = varEnt.getValue();
+								String refVarName = null;
+								for (ChannelMember refCm: ((DataTransferChannel) ch).getReferenceChannelMembers()) {
+									Expression varExp = refCm.getStateTransition().getMessageExpression().getSubTerm(varEnt.getKey());
+									if (varExp != null && varExp instanceof Variable) {
+										if (refCm.getStateTransition().getCurStateExpression().contains(varExp)) {
+											refVarName = refCm.getResource().getResourceName();
+											break;
+										}
+									}
+								}
+								if (refVarName != null) {
+									// var has come from a reference resource.
+									VariableDeclaration param = new VariableDeclaration(var.getType(), refVarName);
+									resInputParams.add(param);
+								} else {
+									// var has not come from reference resource.
+									String paramName = var.getName();
+									VariableDeclaration param = new VariableDeclaration(var.getType(), paramName);
+									resInputParams.add(param);
+									param = new VariableDeclaration(var.getType(), paramName);
+									param.addAnnotation(new Annotation("FormParam", "\"" + paramName + "\""));
+									rootInputParams.add(param);
+								}
 							}
 							
 							if (rn.getResourceHierarchy().getParent() != null && rn.getResourceHierarchy().getParent().getParent() != null) {
diff --git a/AlgebraicDataflowArchitectureModel/src/generators/JerseyMethodBodyGenerator.java b/AlgebraicDataflowArchitectureModel/src/generators/JerseyMethodBodyGenerator.java
index a04e044..e04d2c6 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/JerseyMethodBodyGenerator.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/JerseyMethodBodyGenerator.java
@@ -288,16 +288,24 @@
 											if (!chainedCalls.contains(srcUpdate)) {
 												// The first call to an update method in this method
 												// Value of the source side (input side) resource.
-												params.add(0, new AbstractMap.SimpleEntry<>(src.getResourceStateType(), new AbstractMap.SimpleEntry<>(srcResourceName, "this.value")));
+												params.add(0, new AbstractMap.SimpleEntry<>(src.getResourceStateType(), 
+																							new AbstractMap.SimpleEntry<>(JerseyCodeGenerator.toVariableName(srcResourceName), "this.value")));
 												srcUpdate.addStatement(getHttpMethodParamsStatement(srcComponent.getTypeName(), params, true));
-												srcUpdate.addStatement("String result = " + getHttpMethodCallStatement(baseURL, dstResourceName, srcResName, httpMethod));
+												srcUpdate.addStatement("String result = " + getHttpMethodCallStatement(baseURL, 
+																														JerseyCodeGenerator.toVariableName(dstResourceName), 
+																														JerseyCodeGenerator.toVariableName(srcResName), 
+																														httpMethod));
 												chainedCalls.add(srcUpdate);
 											} else {
 												// After the second time of call to update methods in this method
 												// Value of the source side (input side) resource.
-												params.add(0, new AbstractMap.SimpleEntry<>(src.getResourceStateType(), new AbstractMap.SimpleEntry<>(srcResourceName, "this.value")));
+												params.add(0, new AbstractMap.SimpleEntry<>(src.getResourceStateType(), 
+																							new AbstractMap.SimpleEntry<>(JerseyCodeGenerator.toVariableName(srcResourceName), "this.value")));
 												srcUpdate.addStatement(getHttpMethodParamsStatement(srcComponent.getTypeName(), params, false));
-												srcUpdate.addStatement("result = " + getHttpMethodCallStatement(baseURL, dstResourceName, srcResName, httpMethod));
+												srcUpdate.addStatement("result = " + getHttpMethodCallStatement(baseURL, 
+																												JerseyCodeGenerator.toVariableName(dstResourceName), 
+																												JerseyCodeGenerator.toVariableName(srcResName), 
+																												httpMethod));
 											}
 											srcUpdate.addThrow("JsonProcessingException");
 										}
@@ -330,16 +338,24 @@
 										if (!chainedCalls.contains(srcInput)) {
 											// First call to an update method in this method
 											// Value of the source side (input side) resource.
-											params.add(0, new AbstractMap.SimpleEntry<>(src.getResourceStateType(), new AbstractMap.SimpleEntry<>(srcResourceName, "this.value")));
+											params.add(0, new AbstractMap.SimpleEntry<>(src.getResourceStateType(), 
+																						new AbstractMap.SimpleEntry<>(JerseyCodeGenerator.toVariableName(srcResourceName), "this.value")));
 											srcInput.addStatement(getHttpMethodParamsStatement(srcComponent.getTypeName(), params, true));
-											srcInput.addStatement("String result = " + getHttpMethodCallStatement(baseURL, dstResourceName, srcResName, httpMethod));
+											srcInput.addStatement("String result = " + getHttpMethodCallStatement(baseURL, 
+																													JerseyCodeGenerator.toVariableName(dstResourceName), 
+																													JerseyCodeGenerator.toVariableName(srcResName), 
+																													httpMethod));
 											chainedCalls.add(srcInput);
 										} else {
 											// After the second time of call to update methods in this method
 											// Value of the source side (input side) resource.
-											params.add(0, new AbstractMap.SimpleEntry<>(src.getResourceStateType(), new AbstractMap.SimpleEntry<>(srcResourceName, "this.value")));
+											params.add(0, new AbstractMap.SimpleEntry<>(src.getResourceStateType(), 
+																						new AbstractMap.SimpleEntry<>(JerseyCodeGenerator.toVariableName(srcResourceName), "this.value")));
 											srcInput.addStatement(getHttpMethodParamsStatement(srcComponent.getTypeName(), params, false));
-											srcInput.addStatement("result = " + getHttpMethodCallStatement(baseURL, dstResourceName, srcResName, httpMethod));
+											srcInput.addStatement("result = " + getHttpMethodCallStatement(baseURL, 
+																											JerseyCodeGenerator.toVariableName(dstResourceName), 
+																											JerseyCodeGenerator.toVariableName(srcResName), 
+																											httpMethod));
 										}
 										srcInput.addThrow("JsonProcessingException");
 									}
@@ -507,7 +523,24 @@
 						}
 						if (input != null) {
 							// In each resource
-							Expression updateExp = entry.getKey().deriveUpdateExpressionOf(out, JerseyCodeGenerator.pushAccessor);
+							Set<ResourcePath> referredSet = referredResources.get(input);
+							for (ChannelMember rc: entry.getKey().getReferenceChannelMembers()) {
+								// For each reference channel member, get the current state of the reference side resource by pull data transfer.
+								ResourcePath ref = rc.getResource();
+								if (referredSet == null) {
+									referredSet = new HashSet<>();
+									referredResources.put(input, referredSet);
+								}
+								if (!out.getResource().equals(ref)) {
+									String refResourceName = ref.getResourceName();
+									Type refResourceType = ref.getResourceStateType();
+									if (!referredSet.contains(ref)) {
+										referredSet.add(ref);
+										generatePullDataTransfer(input, refResourceName, refResourceName, refResourceType);
+									}
+								}
+							}
+							Expression updateExp = entry.getKey().deriveUpdateExpressionOf(out, JerseyCodeGenerator.refAccessor);
 							// Replace Json constructor with a constructor of the child resource.
 							ResourceHierarchy outRes = out.getResource().getResourceHierarchy();
 							if (outRes.getChildren().size() == 1 && outRes.getChildren().iterator().next().getNumParameters() > 0) {
@@ -530,7 +563,7 @@
 									updateStatement = sideEffects[0] + "this.value = " + newState + ";";
 								}
 								if (input.getBody() == null || !input.getBody().getStatements().contains(updateStatement)) {
-									input.addFirstStatement(updateStatement);
+									input.addStatement(updateStatement);
 								}
 							} else {
 								String updateStatement = null;
@@ -558,7 +591,7 @@
 										updateStatement = sideEffects[0] + "this." + JerseyCodeGenerator.toVariableName(JerseyCodeGenerator.getComponentName(resource)) + " = " + newState + ";";
 									}
 									if (updateStatement != null && (input.getBody() == null || !input.getBody().getStatements().contains(updateStatement))) {
-										input.addFirstStatement(updateStatement);
+										input.addStatement(updateStatement);
 									}
 								}
 							}