diff --git a/AlgebraicDataflowArchitectureModel/src/models/algebra/Term.java b/AlgebraicDataflowArchitectureModel/src/models/algebra/Term.java
index 9cc7de2..2a22051 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/algebra/Term.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/algebra/Term.java
@@ -385,7 +385,7 @@
 			if (implParamOrder == null) {
 				String exp = null;
 				String receiver = "";
-				if (children.get(0) != null) {
+				if (children.size() > 0 && children.get(0) != null) {
 					receiver = children.get(0).toImplementation(sideEffects);
 					exp = receiver + "." + symbol.toImplementation() + "(";
 				} else {