Lewis & Short

at-testor, ātus, 1, v. dep., to bear witness to, to attest, prove, confirm, corroborate (very rare, and not before the Aug. per.; for in Cic. Sull. 29 fin. the reading should be, with Cod. Erf. and Lambin., ad testandam omnium memoriam; v. Frotsch. ad h. l.; so B. and K.): hoc attestatur brevis Aesopi fabula, Phaedr. 1, 10, 3: Plin. H. N. praef. § 10: M. Cato id saepenumero attestatus est, Gell. 4, 12: attestata fulgura, in the lang. of omens, lightnings which confirm that which was indicated by previous lightnings, confirmatory (opp. peremptalibus, which cancel, annul, what was previously indicated): attestata (fulmina), quae prioribus consentiunt, Sen. Q. N. 2, 49: attestata dicebantur fulgura, quae iterato fiebant, videlicet significationem priorum attestantia, Paul. ex Fest. p. 12 Müll.; cf. Müll. Etrusk. 2, p. 170.