diff --git a/CryptClass/AbstractSKA.hpp b/CryptClass/AbstractSKA.hpp
index ca7230b..5a23c36 100644
--- a/CryptClass/AbstractSKA.hpp
+++ b/CryptClass/AbstractSKA.hpp
@@ -7,28 +7,33 @@
  * Specify which method the algorithm must be implement.
  *
  */
+
 #ifndef __AbstractSKA__
 #define __AbstractSKA__
 
+
+//----- std -----
 #include <string>
 
 
+
 /**
  * @class AbstractSKA AbstractSKA.hpp "/CryptClass/AbstractSKA.hpp"
  * @brief Class for Symmetric-Key Algorithm (SKA)
  * @author manzerbredes
  *
- * This class should not be instanciate directly.
+ * This class should not be instantiate directly.
  *
  */
-
 class AbstractSKA {
 
     public:
-        AbstractSKA(){
-        }
-        ~AbstractSKA(){
-        }
+        //Constructor
+        AbstractSKA();
+
+        //Destructor
+        ~AbstractSKA();
+
 
        /**
         * @brief Encrypt data.
@@ -42,6 +47,7 @@ class AbstractSKA {
         */
         virtual std::string encrypt(std::string key, std::string data) = 0;
 
+
        /**
         * @brief Decrypt data.
         *