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) {