diff --git a/CodingStandards.md b/CodingStandards.md
index 8ebd4c3..32602e0 100644
--- a/CodingStandards.md
+++ b/CodingStandards.md
@@ -30,7 +30,7 @@ from allmydata.util.assertutil import _assert, precondition, postcondition
 # your code here
 ```
 
- * Do not include a per-file copyright header (they just get out of date and are redundant with source:README.txt).
+ * Do not include a per-file copyright header (they just get out of date and are redundant with source:README.rst).
  * Put two blank lines between classes.
  * Put one blank line before a block comment if the preceding line is code at the same indent level (this makes it harder to mistake the code as part of the comment, and makes the comment easier to read). 
  * Feel free to ignore the part of PEP-8 that says to put each module import on a separate line, but don't import modules from multiple separate packages on the same line.