diff --git a/src/Utils/String.cpp b/src/Utils/String.cpp
index 67d35006..135458a7 100644
--- a/src/Utils/String.cpp
+++ b/src/Utils/String.cpp
@@ -104,7 +104,7 @@ namespace Utils
 		}
 
 		// trim from start
-		std::string &LTrim(std::string &s)
+		std::string& LTrim(std::string& s)
 		{
 			s.erase(s.begin(), std::find_if(s.begin(), s.end(), [](int val)
 			{
@@ -114,7 +114,7 @@ namespace Utils
 		}
 
 		// trim from end
-		std::string &RTrim(std::string &s)
+		std::string& RTrim(std::string& s)
 		{
 			s.erase(std::find_if(s.rbegin(), s.rend(), [](int val)
 			{
@@ -124,7 +124,7 @@ namespace Utils
 		}
 
 		// trim from both ends
-		std::string &Trim(std::string &s)
+		std::string& Trim(std::string& s)
 		{
 			return LTrim(RTrim(s));
 		}
diff --git a/src/Utils/String.hpp b/src/Utils/String.hpp
index 3beed27e..8374500a 100644
--- a/src/Utils/String.hpp
+++ b/src/Utils/String.hpp
@@ -81,9 +81,9 @@ namespace Utils
 		std::vector<std::string> Split(const std::string& str, const char delim);
 		void Replace(std::string &string, const std::string& find, const std::string& replace);
 		bool StartsWith(const std::string& haystack, const std::string& needle);
-		std::string &LTrim(std::string &s);
-		std::string &RTrim(std::string &s);
-		std::string &Trim(std::string &s);
+		std::string& LTrim(std::string& s);
+		std::string& RTrim(std::string& s);
+		std::string& Trim(std::string& s);
 
 		std::string FormatTimeSpan(int milliseconds);
 		std::string FormatBandwidth(size_t bytes, int milliseconds);