diff --git a/libsolidity/AST.cpp b/libsolidity/AST.cpp
index 0b635339d..5bba8dce7 100644
--- a/libsolidity/AST.cpp
+++ b/libsolidity/AST.cpp
@@ -255,7 +255,7 @@ TypeError ASTNode::createTypeError(string const& _description)
 	return TypeError() << errinfo_sourceLocation(getLocation()) << errinfo_comment(_description);
 }
 
-void Statement::expectType(Expression& _expression, const Type& _expectedType)
+void Statement::expectType(Expression& _expression, Type const& _expectedType)
 {
 	_expression.checkTypeRequirements();
 	if (!_expression.getType()->isImplicitlyConvertibleTo(_expectedType))
diff --git a/libsolidity/AST.h b/libsolidity/AST.h
index e66572800..e72826602 100644
--- a/libsolidity/AST.h
+++ b/libsolidity/AST.h
@@ -89,7 +89,7 @@ public:
 		ASTNode(_location), m_name(_name) {}
 
 	/// Returns the declared name.
-	const ASTString& getName() const { return *m_name; }
+	ASTString const& getName() const { return *m_name; }
 
 private:
 	ASTPointer<ASTString> m_name;
@@ -259,7 +259,7 @@ public:
 	virtual void accept(ASTVisitor& _visitor) override;
 	virtual std::shared_ptr<Type> toType() override { return Type::fromUserDefinedTypeName(*this); }
 
-	const ASTString& getName() const { return *m_name; }
+	ASTString const& getName() const { return *m_name; }
 	void setReferencedStruct(StructDefinition& _referencedStruct) { m_referencedStruct = &_referencedStruct; }
 	StructDefinition const* getReferencedStruct() const { return m_referencedStruct; }
 
@@ -549,7 +549,7 @@ public:
 				 ASTPointer<ASTString> const& _memberName):
 		Expression(_location), m_expression(_expression), m_memberName(_memberName) {}
 	virtual void accept(ASTVisitor& _visitor) override;
-	const ASTString& getMemberName() const { return *m_memberName; }
+	ASTString const& getMemberName() const { return *m_memberName; }
 	virtual void checkTypeRequirements() override;
 
 private:
diff --git a/libsolidity/ASTPrinter.h b/libsolidity/ASTPrinter.h
index 97256c056..d788ba76c 100644
--- a/libsolidity/ASTPrinter.h
+++ b/libsolidity/ASTPrinter.h
@@ -38,7 +38,7 @@ class ASTPrinter: public ASTVisitor
 public:
 	/// Create a printer for the given abstract syntax tree. If the source is specified,
 	/// the corresponding parts of the source are printed with each node.
-	ASTPrinter(ASTPointer<ASTNode> const& _ast, const std::string& _source = std::string());
+	ASTPrinter(ASTPointer<ASTNode> const& _ast, std::string const& _source = std::string());
 	/// Output the string representation of the AST to _stream.
 	void print(std::ostream& _stream);
 
diff --git a/libsolidity/Scanner.h b/libsolidity/Scanner.h
index fbaba9ed6..c08d3219e 100644
--- a/libsolidity/Scanner.h
+++ b/libsolidity/Scanner.h
@@ -124,7 +124,7 @@ public:
 	/// Returns the current token
 	Token::Value getCurrentToken() { return m_current_token.token; }
 	Location getCurrentLocation() const { return m_current_token.location; }
-	const std::string& getCurrentLiteral() const { return m_current_token.literal; }
+	std::string const& getCurrentLiteral() const { return m_current_token.literal; }
 	///@}
 
 	///@{
@@ -133,7 +133,7 @@ public:
 	/// Returns the next token without advancing input.
 	Token::Value peekNextToken() const { return m_next_token.token; }
 	Location peekLocation() const { return m_next_token.location; }
-	const std::string& peekLiteral() const { return m_next_token.literal; }
+	std::string const& peekLiteral() const { return m_next_token.literal; }
 	///@}
 
 	///@{
diff --git a/test/solidityCompiler.cpp b/test/solidityCompiler.cpp
index 0d9d59c1c..22828238a 100644
--- a/test/solidityCompiler.cpp
+++ b/test/solidityCompiler.cpp
@@ -71,7 +71,7 @@ private:
 	Expression* m_expression;
 };
 
-bytes compileFirstExpression(const std::string& _sourceCode)
+bytes compileFirstExpression(std::string const& _sourceCode)
 {
 	Parser parser;
 	ASTPointer<ContractDefinition> contract;
diff --git a/test/solidityNameAndTypeResolution.cpp b/test/solidityNameAndTypeResolution.cpp
index 833ae6d4b..9e34e6d0e 100644
--- a/test/solidityNameAndTypeResolution.cpp
+++ b/test/solidityNameAndTypeResolution.cpp
@@ -38,7 +38,7 @@ namespace test
 
 namespace
 {
-void parseTextAndResolveNames(const std::string& _source)
+void parseTextAndResolveNames(std::string const& _source)
 {
 	Parser parser;
 	ASTPointer<ContractDefinition> contract = parser.parse(
diff --git a/test/solidityParser.cpp b/test/solidityParser.cpp
index 701a6e76c..4ca9370d6 100644
--- a/test/solidityParser.cpp
+++ b/test/solidityParser.cpp
@@ -37,7 +37,7 @@ namespace test
 
 namespace
 {
-ASTPointer<ASTNode> parseText(const std::string& _source)
+ASTPointer<ASTNode> parseText(std::string const& _source)
 {
 	Parser parser;
 	return parser.parse(std::make_shared<Scanner>(CharStream(_source)));