i don't have a "hard" reference in the manuals but the RA 1+2 FAULT description in the FCTM comes to my mind in a trice.
Furthermore, the final stages of the approach should be flown using raw data in order to avoid possible excessive roll rates if LOC is still engaged. Indeed, as the autopilot gains are no longer updated with the radio altimeter signal, the AP/FD behaviour may be unsatisfactory when approaching the ground.
FCTM/AO-Abnormal Operations/AO 034-NAVIGATION/DUAL RADIO ALTIMETER FAILURE