diff --git a/README.md b/README.md
index 176f269..f41d540 100644
--- a/README.md
+++ b/README.md
@@ -19,7 +19,7 @@ This "database" depends on a few simple ideas:
 1. A sequentially numbered filename specification which serves as unique id, like this: `001.foo.md`.  The filesystem is the database. Note that the string descriptor is optional. In regex terms:
 
     ```sh
-    ls | egrep '^[[:digit:]]+\.?.*\.md|txt'
+    ls | egrep '^[[:digit:]]+\.?.*\.md'
     ```
 
     Or: