diff --git a/src/baseexpression.h b/src/baseexpression.h
index faf50f1..c6e9534 100644
--- a/src/baseexpression.h
+++ b/src/baseexpression.h
@@ -204,7 +204,11 @@ public:
 	}
 
 
-
+	/*
+	 * IMPLEMENT ME
+	 * esc for: signed char, wchar_t, char16_t, char32_t
+	 *
+	 */
 	virtual void esc(char val, 					PT::TextStream & stream);
 	virtual void esc(unsigned char val, 		PT::TextStream & stream);
 
@@ -608,6 +612,11 @@ protected:
 	virtual void put_name_value_separator();
 
 
+	/*
+	 * IMPLEMENT ME
+	 * put_type for: signed char, wchar_t, char16_t, char32_t
+	 *
+	 */
 	virtual void put_type(char val, 				PT::TextStream & stream);
 	virtual void put_type(unsigned char val, 		PT::TextStream & stream);
 
diff --git a/src/model.h b/src/model.h
index 0062565..0911cbe 100644
--- a/src/model.h
+++ b/src/model.h
@@ -213,6 +213,11 @@ protected:
 
 
 	/////////////////////////////////
+	/*
+	 * IMPLEMENT ME
+	 * field methods for such field_values: signed char, wchar_t, char16_t, char32_t, std::u16string, std::u32string
+	 *
+	 */
 
 	void field(const wchar_t * field_name, char & field_value, bool insertable = true, bool updatable = true, bool is_primary_key = false)
 	{