diff --git a/alib2data/src/label/LabelPairLabel.cpp b/alib2data/src/label/LabelPairLabel.cpp
index 1685ae410aa6f3b2cb9343e399497412e9340b52..965950b5897339abe22d5be6bc0d93d56147ec61 100644
--- a/alib2data/src/label/LabelPairLabel.cpp
+++ b/alib2data/src/label/LabelPairLabel.cpp
@@ -23,7 +23,7 @@ LabelBase* LabelPairLabel::plunder() && {
 	return new LabelPairLabel(std::move(*this));
 }
 
-std::pair<Label, Label> LabelPairLabel::getData() const {
+const std::pair<Label, Label>& LabelPairLabel::getData() const {
 	return label;
 }
 
diff --git a/alib2data/src/label/LabelPairLabel.h b/alib2data/src/label/LabelPairLabel.h
index b1032020cdbd3c304f28789549bbdb89d9969fec..3eab974e0296dc04c7cb0fbc11bd8faaf4e29048 100644
--- a/alib2data/src/label/LabelPairLabel.h
+++ b/alib2data/src/label/LabelPairLabel.h
@@ -43,7 +43,7 @@ public:
 	/**
 	 * @return name of the symbol
 	 */
-	std::pair<Label, Label> getData() const;
+	const std::pair<Label, Label>& getData() const;
 
 	virtual bool operator <(const LabelPairLabel& other) const;
 	virtual bool operator ==(const LabelPairLabel& other) const;
diff --git a/alib2data/src/label/LabelSetLabel.cpp b/alib2data/src/label/LabelSetLabel.cpp
index 7f87d67f3db7ee8de79eb0b0494edb9dbef5b52c..3ee80e4b4931a9eece77053c1f5e408d4b002a22 100644
--- a/alib2data/src/label/LabelSetLabel.cpp
+++ b/alib2data/src/label/LabelSetLabel.cpp
@@ -23,7 +23,7 @@ LabelBase* LabelSetLabel::plunder() && {
 	return new LabelSetLabel(std::move(*this));
 }
 
-std::set<Label> LabelSetLabel::getData() const {
+const std::set<Label>& LabelSetLabel::getData() const {
 	return label;
 }
 
diff --git a/alib2data/src/label/LabelSetLabel.h b/alib2data/src/label/LabelSetLabel.h
index 783fd226c4f2e6c8bc5c918c20e898df72ff855e..51281a7a14d1d427f62c40e8acfd20c358e5a10b 100644
--- a/alib2data/src/label/LabelSetLabel.h
+++ b/alib2data/src/label/LabelSetLabel.h
@@ -43,7 +43,7 @@ public:
 	/**
 	 * @return name of the symbol
 	 */
-	std::set<Label> getData() const;
+	const std::set<Label>& getData() const;
 
 	virtual bool operator <(const LabelSetLabel& other) const;
 	virtual bool operator ==(const LabelSetLabel& other) const;