The following url is hardcoded in the mongodb server code:
http://dochub.mongodb.org/core/resyncingaverystalereplicasetmember

Today, that link seems to redirect to this:
http://docs.mongodb.org/manual/administration/replica-sets/#replica-set-resync-stale-member

However, that page no longer has that particular anchor on it. Instead, I think it probably should redirect to:
http://docs.mongodb.org/manual/tutorial/resync-replica-set-member/