Need reference for the two conditions need to realize path to Nibbana

In this article , it has mentioned that; >During the time of the Buddha there were two ways by which one could understand the Dhamma and realise the path to Nibbana. One is called “paratoghosa paccaya.” Hearing the true Dhamma from others who know it. The other is called “sammasati” or practice of meditation. Would anyone please give me reference from Pali canon or any other book for the above statement?