diff --git a/SftpFrontend.md b/SftpFrontend.md
index 2f80aa5..d2cd7f1 100644
--- a/SftpFrontend.md
+++ b/SftpFrontend.md
@@ -54,7 +54,7 @@ sshfs is an SFTP client that allows filesystem access via FUSE (a user-space fil
 
 Tahoe's SFTP frontend includes several workarounds and extensions to make it function correctly with sshfs.
 
-Mutable parts of a filesystem should only be accessed via a single sshfs mount (this is a stronger restriction than the [write coordination directive](http://tahoe-lafs.org/source/tahoe-lafs/trunk/docs/write_coordination.html) against writing mutable parts of a filesystem via more than one gateway). Data loss may result for concurrently accessed files if this restriction is not followed.
+Mutable parts of a filesystem should only be accessed via a single sshfs mount (this is a stronger restriction than the [write coordination directive](http://tahoe-lafs.org/trac/tahoe-lafs/browser/trunk/docs/write_coordination.rst) against writing mutable parts of a filesystem via more than one gateway). Data loss may result for concurrently accessed files if this restriction is not followed.
 
 When writing a file to the Tahoe filesystem, sshfs does not wait for the 'close' request to complete before reporting to the application that the file has been successfully closed (#1059). Therefore, you should not shut down your gateway node immediately after writing files via sshfs, otherwise those files may be lost. It is possible that an upload could fail (due to a network error, lack of storage space, etc.); such failures will not be reported to applications using sshfs. This also implies that during the upload, a file could be visible via SFTP but not via the Tahoe WUI, CLI, or FTP frontends.