+@node version in documentation files
+@section @code{\version} in documentation files
+
+Every documentation file which includes LilyPond code should begin
+with a @code{\version} statement referencing a version of LilyPond
+consistent with the syntax of the contained code.
+
+The @code{\version} statement should be commented out to avoid
+creating problems when building releases with GUB, like this:
+
+@example
+%c \version "2.19.1"
+@end example
+
+So, if you are adding LilyPond code which is not consistent with the
+current version header, you should
+
+@enumerate
+
+@item
+run convert-ly on the file using the latest version of LilyPond
+(which should, if everybody has done proper maintenance, not change
+anything);
+
+@item
+add the new code;
+
+@item
+modify the version number to match the new code.
+
+@end enumerate
+
+