Can a prosecutor vouch for the credibility of witnesses by referring to evidence that is not in the record?

"It is settled that '[a] prosecutor is prohibited from vouching for the credibility of witnesses or otherwise bolstering the veracity of their testimony by referring to evidence outside the record. [Citations.] Nor is a prosecutor permitted to place the prestige of [his or her] office behind a witness by offering the impression that [he or she] has taken steps to assure a witness's truthfulness at trial. [Citation.] However, so long as a prosecutor's assurances regarding the apparent honesty or reliability of prosecution witnesses are based on the "facts of [the] record and the inferences reasonably drawn therefrom, rather than any purported personal knowledge or belief," [his or her] comments cannot be characterized as improper vouching.' " (People v. Caldwell (2013) 212 Cal.App.4th 1262, 1269-1270.)