diff --git a/docs/MANUAL b/docs/MANUAL
index ce63326eb57600f5f4586d9a0aa857da454c5153..b58c4fb861003150397873c1afc206d01a256d1e 100644
--- a/docs/MANUAL
+++ b/docs/MANUAL
@@ -689,7 +689,7 @@ ENVIRONMENT VARIABLES
 
   Curl reads and understands the following environment variables:
 
-        HTTP_PROXY, HTTPS_PROXY, FTP_PROXY, GOPHER_PROXY
+        http_proxy, HTTPS_PROXY, FTP_PROXY, GOPHER_PROXY
 
   They should be set for protocol-specific proxies. General proxy should be
   set with