Evidences of Praecepta that it has came from Master Himself ! Swami Yogananda writes as fast as he receives them from the Infinite.

I am organizing a correspondence course here, exactly like ours. Dick is working hard setting up the correspondence course of Praecepta Lessons like that in America. (1934)

Footnote of the same letter : (Paramhansaji writes about the “correspondence course,” the mailing from Ranchi of the printed Yogoda Lessons, which he prepared with the assistance of Dick Wright when they were in India.)

Paramhansa Yogananda to Rajarshi Janakananda in the book (Rajarshi Janakananda- A great Western Yogi- letter of January 5, 1936)

Though CC (correspondence course) has not paid yet, it has immortalized the Lessons, which I would not have written without proper incentive. Even in the circle of saints, I hear highest praises about the Lessons, for systematizing the steps of realization so scattered and buried...