diff --git a/scripts/bootstrapit_update.sh b/scripts/bootstrapit_update.sh
index 63be552..07b460c 100644
--- a/scripts/bootstrapit_update.sh
+++ b/scripts/bootstrapit_update.sh
@@ -244,6 +244,7 @@ fi
 
 # strip off ":latest"
 # https://medium.com/@mccode/the-misunderstood-docker-tag-latest-af3babfd6375
+# https://vsupalov.com/docker-latest-tag/
 DOCKER_BASE_IMAGE="$(dirname ${DOCKER_BASE_IMAGE})"/"$(basename ${DOCKER_BASE_IMAGE} ':latest')";
 
 if [[ -z "$MODULE_NAME" ]]; then