Council of Trent: Session VII, Reformation, Chapter XI

CHAPTER XI. Faculties for promotion shall not avail any one without a just cause.

Faculties, for being promoted (to orders) by any prelate whatsoever, shall be of no avail but to those who have a lawful cause-which is to be expressed in their letters-why they cannot be ordained by their own bishops; and even then they shall not be ordained but by a bishop who is resident in his own diocese, or by him who exercises the pontifical functions for him, and after having undergone a previous careful examination.

Translation: J. Waterworth, The Canons and Decrees of the Council of Trent (1848), Hanover Historical Texts Project transcription (1995).