diff --git a/doc/source/formats.rst b/doc/source/formats.rst
index 123becc..5c07b14 100644
--- a/doc/source/formats.rst
+++ b/doc/source/formats.rst
@@ -27,12 +27,9 @@ File name
 ---------
 
 Each file is named with the attribute associated to the data it contains, and the number of 
-its version, separated by an underscore.
+its version, separated by an ``@``, and with the extension ``.odc``.
 
-Example : ``count_0003``
-
-.. todo::
-	Filename extension?
+Example : ``count@3.odc``
 
 
 Header
@@ -62,7 +59,7 @@ Versioning
 Since OBIDMS column files are read-only, any modification leads to the creation of a new version 
 of the column file.
 
-The first version of a column file is numbered 0001, and each new version increments that 
+The first version of a column file is numbered 1, and each new version increments that 
 number by 1.