diff --git a/src/outliers.h b/src/outliers.h
index 1c00ad244575449d919ff5ca238b3856ba348001..d78945f60563d538d6dccbd75d2bc0eb45df9fd7 100644
--- a/src/outliers.h
+++ b/src/outliers.h
@@ -5,8 +5,8 @@
 #ifndef UEBUNG5_OUTLIERS_H
 #define UEBUNG5_OUTLIERS_H
 
+#include <cstddef>
 #include <vector>
-#include "cstddef"
 
 double findNMin(const std::vector<double>& data, size_t n);
 double findNMax(const std::vector<double>& data, size_t n);
diff --git a/src/statistics.cpp b/src/statistics.cpp
index a804544c849687a6daaf9e24d2ab6bfdf1fee066..2bcb5a0ff9e259168e27c295b56261b20bcffcc9 100644
--- a/src/statistics.cpp
+++ b/src/statistics.cpp
@@ -1,8 +1,6 @@
 #include "statistics.h"
-#include "cstddef"
+
 #include <algorithm>
 #include <numeric>
 
-size_t countValuesNearMean(const std::vector<double>& data) {
-    return 0;
-}
+size_t countValuesNearMean(const std::vector<double>& data) { return 0; }
diff --git a/src/statistics.h b/src/statistics.h
index 5c72e3704ab3bab6178eea14792d82ee4fe411ae..a236a324ff1f731a6fac7104d3427bebe6f20ca0 100644
--- a/src/statistics.h
+++ b/src/statistics.h
@@ -1,8 +1,8 @@
 #ifndef STATISTICS_H
 #define STATISTICS_H
 
+#include <cstddef>
 #include <vector>
-#include "cstddef"
 
 size_t countValuesNearMean(const std::vector<double>& data);