diff --git a/README.md b/README.md
index 1c5b774..c24be18 100644
--- a/README.md
+++ b/README.md
@@ -150,7 +150,7 @@ The options are as follows:
 
 **-S** *sources*
 
-> use specified sources only (recommended: RIPE,AFRINIC,ARIN,APNIC,LACNIC,RIPE).
+> use specified sources only (recommended: RPKI,AFRINIC,ARIN,APNIC,LACNIC,RIPE).
 
 **-t**