In 2021, I traveled with Nagato Sensei to the USA for a training event hosted by the Dayton Bujinkan Dojo. At the event's banquet, I was invited to speak about Hatsumi Sensei's art. This is a video of that speech including pages from the Earth book. At the time of the speech, Earth hadn't been printed yet, so the images are samples.
A streaming video of the event with Nagato Sensei is available with the Dayton Dojo (details are HERE).
— Steve