Lewis Short
prŏbātōrĭa (noun F) : (sc. epistula) [id.]
* A letter of recommendation (from the emperor), a certificate of qualification (postclass.): sacra probatoria,Cod. Just. 12, 58, 2: emissa sacri scrinii probatoria,ib. 12, 60, 6; 12, 36, 7.
Charlton T. Lewis, Charles Short, A Latin Dictionary