diff --git a/README.md b/README.md
index adfc8cd..ea6865d 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,7 @@
 # timeRequest
 
 Test sketch ro request time from [MySensors](https://www.mysensors.org/) master node.
+
+## external libraries
+- [MySensors](https://github.com/mysensors/MySensors)
+- [Time](https://github.com/PaulStoffregen/Time)