[CALLISTRATUS libro primo quaestionum. ] §12.3.10.prIn instrumentis, quae quis non exhibet, actori permittitur in litem iurare, quanti sua interest ea proferri, ut tanti condemnetur reus: idque etiam diuus Commodus rescripsit.
[CALLISTRATUS, First Book of Questions.] In the case of documents which someone does not produce, the plaintiff is permitted to take an oath in court as to how much it concerns him that they be produced, so that the defendant may be condemned in that amount; and the deified Commodus also stated this in a rescript.