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@@ -93,3 +93,6 @@ Open screen and paste this code:
 # References
 
  * [Lua API](https://github.com/nodemcu/nodemcu-firmware/wiki/nodemcu_api_en)
+ *
+ *
+ * http://blog.3mdeb.com/2015/01/25/esp-12-upgrade-to-esp-iot-sdk-v0-dot-9-5-using-esp-open-sdk-toolchain/