diff --git a/Scripts/Editor/NodeEditorPreferences.cs b/Scripts/Editor/NodeEditorPreferences.cs
index b3026b9..1bba650 100644
--- a/Scripts/Editor/NodeEditorPreferences.cs
+++ b/Scripts/Editor/NodeEditorPreferences.cs
@@ -106,8 +106,24 @@ namespace XNodeEditor {
         private static void PreferencesGUI() {
             VerifyLoaded();
             Settings settings = NodeEditorPreferences.settings[lastKey];
+
+            EditorGUILayout.BeginHorizontal();
+            {
+                EditorGUILayout.Space();
+                {
+                    if (GUILayout.Button(new GUIContent("XNode Documentation", "https://github.com/Siccity/xNode/wiki"),
+                        GUILayout.Width(180)))
+                        Application.OpenURL("https://github.com/Siccity/xNode/wiki");
+
+                    if (GUILayout.Button(
+                        new GUIContent("IcSkill Documentation", "https://github.com/yika-aixi/IcSkillSystem"),
+                        GUILayout.Width(180)))
+                        Application.OpenURL("https://github.com/yika-aixi/IcSkillSystem");
+                }
+                EditorGUILayout.Space();
+            }
+            EditorGUILayout.EndHorizontal();
             
-            if (GUILayout.Button(new GUIContent("Documentation", "https://github.com/Siccity/xNode/wiki"), GUILayout.Width(100))) Application.OpenURL("https://github.com/Siccity/xNode/wiki");
             EditorGUILayout.Space();
 
             NodeSettingsGUI(lastKey, settings);