I.-When the holder of an external radiotherapy authorisation carries out treatments under stereotactic conditions, it must have at least two particle machines, at least one of which must be capable of carrying out radiotherapy treatments under stereotactic conditions.
II – If the holder performs intracranial radiotherapy under stereotactic conditions for primary brain tumours, a protocol is drawn up in advance with doctors specialising in neurosurgery who perform intracranial radiosurgery under stereotactic conditions in accordance with article R. 6123-100.