diff --git a/server/db_template.sql b/server/db_template.sql
index 05a7193..0ffafd3 100644
--- a/server/db_template.sql
+++ b/server/db_template.sql
@@ -1,3 +1,4 @@
+-- See for data provided by TTN https://www.thethingsnetwork.org/docs/applications/mqtt/api.html
 CREATE TABLE readings IF NOT EXISTS (
 	id INTEGER PRIMARY KEY, -- Random unique integer
 	lat FLOAT NOT NULL, -- Latitude component of GPS co-ordinates of reading