diff --git a/src/main/java/de/tlc4b/TLC4B.java b/src/main/java/de/tlc4b/TLC4B.java
index 9efea70a50f7580fa3719a2f91c954de2e1deef0..51094754bc91e5e537d432e4a02fdad1a847da3f 100644
--- a/src/main/java/de/tlc4b/TLC4B.java
+++ b/src/main/java/de/tlc4b/TLC4B.java
@@ -13,17 +13,25 @@ import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.util.Map;
 import java.util.Map.Entry;
-import java.util.concurrent.*;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
 
 import de.be4.classicalb.core.parser.exceptions.BCompoundException;
-import de.tlc4b.analysis.UsedStandardModules.STANDARD_MODULES;
-import de.tlc4b.exceptions.TLC4BIOException;
 import de.tlc4b.exceptions.TLC4BException;
+import de.tlc4b.exceptions.TLC4BIOException;
 import de.tlc4b.exceptions.TranslationException;
 import de.tlc4b.tlc.TLCOutputInfo;
 import de.tlc4b.tlc.TLCResults;
 import de.tlc4b.util.StopWatch;
-import org.apache.commons.cli.*;
+
+import org.apache.commons.cli.CommandLine;
+import org.apache.commons.cli.DefaultParser;
+import org.apache.commons.cli.HelpFormatter;
+import org.apache.commons.cli.Options;
+import org.apache.commons.cli.ParseException;
 
 import static de.tlc4b.TLC4BCliOptions.*;
 import static de.tlc4b.TLC4BCliOptions.TLCOption.*;
@@ -448,8 +456,8 @@ public class TLC4B {
 	}
 
 	private void createStandardModules() {
-		for (STANDARD_MODULES module : translator.getStandardModuleToBeCreated()) {
-			createStandardModule(buildDir, module.toString());
+		for (String module : translator.getStandardModuleToBeCreated()) {
+			createStandardModule(buildDir, module);
 		}
 	}
 
diff --git a/src/main/java/de/tlc4b/Translator.java b/src/main/java/de/tlc4b/Translator.java
index 159f16730f1e0c56280684b4d75679d534047211..b79bbdd4d3134f0512d565b9e33a425a359325aa 100644
--- a/src/main/java/de/tlc4b/Translator.java
+++ b/src/main/java/de/tlc4b/Translator.java
@@ -2,8 +2,8 @@ package de.tlc4b;
 
 import java.io.File;
 import java.io.IOException;
-import java.util.HashSet;
 import java.util.Map;
+import java.util.Set;
 
 import de.be4.classicalb.core.parser.BParser;
 import de.be4.classicalb.core.parser.analysis.prolog.RecursiveMachineLoader;
@@ -21,7 +21,6 @@ import de.tlc4b.analysis.Renamer;
 import de.tlc4b.analysis.Typechecker;
 import de.tlc4b.analysis.UnsupportedConstructsFinder;
 import de.tlc4b.analysis.UsedStandardModules;
-import de.tlc4b.analysis.UsedStandardModules.STANDARD_MODULES;
 import de.tlc4b.analysis.transformation.DefinitionsEliminator;
 import de.tlc4b.analysis.transformation.SeesEliminator;
 import de.tlc4b.analysis.transformation.SequenceSubstitutionsEliminator;
@@ -44,7 +43,7 @@ public class Translator {
 	private String machineName;
 	private String ltlFormula;
 	private PPredicate constantsSetup;
-	private HashSet<STANDARD_MODULES> standardModulesToBeCreated;
+	private Set<String> standardModulesToBeCreated;
 	private TLCOutputInfo tlcOutputInfo;
 	private String translatedLTLFormula;
 
@@ -193,11 +192,7 @@ public class Translator {
 		return tlcOutputInfo;
 	}
 
-	public boolean containsUsedStandardModule(STANDARD_MODULES module) {
-		return standardModulesToBeCreated.contains(module);
-	}
-
-	public HashSet<UsedStandardModules.STANDARD_MODULES> getStandardModuleToBeCreated() {
+	public Set<String> getStandardModuleToBeCreated() {
 		return standardModulesToBeCreated;
 	}
 
diff --git a/src/main/java/de/tlc4b/analysis/UsedStandardModules.java b/src/main/java/de/tlc4b/analysis/UsedStandardModules.java
index b6e2feed50c7a02500df80dd6a83f18f18cf58b4..173d50df689f1750d25a2550d6b979977666a1d7 100644
--- a/src/main/java/de/tlc4b/analysis/UsedStandardModules.java
+++ b/src/main/java/de/tlc4b/analysis/UsedStandardModules.java
@@ -4,6 +4,7 @@ import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 import de.be4.classicalb.core.parser.analysis.DepthFirstAdapter;
 import de.be4.classicalb.core.parser.node.AAddExpression;
@@ -103,8 +104,7 @@ import de.tlc4b.btypes.SetType;
 import de.tlc4b.tla.TLAModule;
 
 public class UsedStandardModules extends DepthFirstAdapter {
-
-	public enum STANDARD_MODULES {
+	private enum STANDARD_MODULES {
 		Naturals, Integers, FiniteSets, Sequences, TLC, BBuiltIns, Relations, FunctionsAsRelations, Functions, SequencesExtended, SequencesAsRelations, ExternalFunctions, Foo
 	}
 
@@ -149,7 +149,7 @@ public class UsedStandardModules extends DepthFirstAdapter {
 		start.apply(this);
 	}
 
-	public ArrayList<STANDARD_MODULES> getExtendedModules() {
+	public List<String> getExtendedModules() {
 		ArrayList<STANDARD_MODULES> list = new ArrayList<>(extendedStandardModules);
 		if (list.contains(STANDARD_MODULES.Integers)) {
 			list.remove(STANDARD_MODULES.Naturals);
@@ -159,10 +159,10 @@ public class UsedStandardModules extends DepthFirstAdapter {
 			Integer i2 = modules.indexOf(s2);
 			return i1.compareTo(i2);
 		});
-		return list;
+		return list.stream().map(STANDARD_MODULES::name).collect(Collectors.toList());
 	}
 
-	public HashSet<STANDARD_MODULES> getStandardModulesToBeCreated() {
+	public Set<String> getStandardModulesToBeCreated() {
 		// dependencies of standard modules
 		HashSet<STANDARD_MODULES> res = new HashSet<>();
 		for (STANDARD_MODULES module : extendedStandardModules) {
@@ -199,7 +199,7 @@ public class UsedStandardModules extends DepthFirstAdapter {
 			}
 
 		}
-		return res;
+		return res.stream().map(STANDARD_MODULES::name).collect(Collectors.toSet());
 	}
 
 	@Override
diff --git a/src/main/java/de/tlc4b/prettyprint/TLAPrinter.java b/src/main/java/de/tlc4b/prettyprint/TLAPrinter.java
index 6cdce49751216c449d6cf60c7b238d73206d7ba2..64da8fd456397e7796aa4d4ed6afe723566b0ebb 100644
--- a/src/main/java/de/tlc4b/prettyprint/TLAPrinter.java
+++ b/src/main/java/de/tlc4b/prettyprint/TLAPrinter.java
@@ -299,15 +299,10 @@ public class TLAPrinter extends DepthFirstAdapter {
 	}
 
 	private void printExtendedModules() {
-		if (!usedStandardModules.getExtendedModules().isEmpty()) {
+		List<String> extendedModules = usedStandardModules.getExtendedModules();
+		if (!extendedModules.isEmpty()) {
 			moduleStringAppend("EXTENDS ");
-			for (int i = 0; i < usedStandardModules.getExtendedModules().size(); i++) {
-				if (i > 0) {
-					moduleStringAppend(", ");
-				}
-				moduleStringAppend(usedStandardModules.getExtendedModules()
-						.get(i).toString());
-			}
+			moduleStringAppend(String.join(", ", extendedModules));
 			moduleStringAppend("\n");
 		}
 	}