That's not a source. The source would be whoever the New York Times talked to, which they actually don't cite:
> This account is based on interviews with people briefed on the surveillance, who spoke on the condition of anonymity because the findings are drawn from classified intelligence, as well as other officials and industry executives and analysts.
> This account is based on interviews with people briefed on the surveillance, who spoke on the condition of anonymity because the findings are drawn from classified intelligence, as well as other officials and industry executives and analysts.