add command for retrieving the sample code

README.md

diff --git a/README.md b/README.md
index 6fefbd1..f8d7651 100644
--- a/README.md
+++ b/README.md
@@ -104,7 +104,11 @@
         G2](https://pki.google.com/roots.pem). In the latter case, you may have
         to manually update the root certificate at times
 
-6.  Retrieve the sample code, place the **BookingService.java** under
+6.  Retrieve the sample code from this repo:
+
+          git clone https://maps-booking.googlesource.com/java-maps-booking-grpc-server-skeleton
+
+    place the **BookingService.java** under
     *src/main/java/ext/maps/booking/partner/v2*, place **Health.java** under
     *src/main/java/grpc/health/v1*. In both files, follow the ***TODOs*** to
     complete your implementations.