Baretti: A dictionary of the English and Italian languages
Accertá-re, v. a.
1. to ascertain, make sure or certain, assure, confirm. — il colpo, to make sure of one's blow; 2. to certify, attest, affirm;v. r. to be certain of, assure one's self of; adv.Accertá-taménte .
Florio: a worlde of wordes, or most copious, dictionarie in Italian and English