From Prabhupada Memories, by H.H Tamal Krsna Maharaja:

In 1977 during his Vyasa Puja in London, I was enumerating a few of Srila Prabhupad’s outstanding accomplishments. At one point he said, “yes, whatever I am doing now, I learned from the time I was a child, from father.”

He added, “Everything, except for one thing, book publishing. That I learned from my Guru Maharaja.”

It was an interesting Vyasa Puja. Srila Prabhupada was ill, and so the Vyasa Puja glorification section was my talk. Somehow Krsna empowered me to speak for 45 minutes on that day. Prabhupada just had me speak. Three times only Srila Prabhupada interrupted. Each time it was to say, “And my Guru Maharaja ordered me to publish books.”

Three times he interrupted my lecture to insert this point, “My Guru Maharaja ordered me to publish books and distribute books.” Three times.

Everything else was fine about the lecture, but somehow he wanted three times to emphasise on the book distribution. Very interesting.