diff --git a/README.md b/README.md
index 84deaa9..afd3e94 100644
--- a/README.md
+++ b/README.md
@@ -145,7 +145,8 @@ Count non successful responses:
 The command-line arguments and flags are intended exclusively to express a requests count query. The configuration, which isn't expected to change across command invocations, is left to environment variables:
 
 - `NGTOP_LOGS_PATH`: path pattern to find the nginx access logs. Defaults to `/var/log/nginx/access.log*`. The pattern is expanded using Go's [`path/filepath.Glob`](https://pkg.go.dev/path/filepath#Glob).
-- `NGTOP_LOG_FORMAT`: The nginx log_format specification to parse the log entries. By default combined logs are assumed, which is equivalent to:
+- `NGTOP_LOG_FORMAT`: The [nginx log_format](https://nginx.org/en/docs/http/ngx_http_log_module.html#log_format "
+") specification to parse the log entries. By default combined logs are assumed, which is equivalent to:
   ```
   NGTOP_LOG_FORMAT='$remote_addr - $remote_user [$time_local] "$request" $status $body_bytes_sent "$http_referer" "$http_user_agent"'
   ```