The Ninpiden (a.k.a. Shinobi Hiden, or Legends of Ninja Secrets) is an authentic ninjutsu manual written by Hattori Hanzō in 1560. It is regarded as one of the three key historical texts of ninjutsu, along with the Shōninki and the Bansenshukai. It was passed down in the Hattori family, and was considered a secret transmission; it was not shared with outsiders and even within the family, few had access to it.
- Anthony Cummins (3 October 2013). The Book of Ninja: The Bansenshukai - Japan's Premier Ninja Manual. Watkins Publishing. p. 14. ISBN 978-1-78028-631-0.
- Martial Arts of the World: R-Z. ABC-CLIO. p. 358. ISBN 978-1-57607-150-2.
- John Man (11 April 2013). Ninja. CORGI BOOKS. p. 354. ISBN 978-0-552-16534-1.
- Kacem Zoughari (30 July 2013). The Ninja: Ancient Shadow Warriors of Japan (The Secret History of Ninjutsu). Tuttle Publishing. p. 364. ISBN 978-1-4629-0287-3.
- Antony Cummins & Yoshie Minami, eds. & trans. The Secret Traditions of the Shinobi: Hattori Hanzo's Shinobi Hiden and Other Ninja Scrolls. Berkeley, Calif.: Blue Snake Books, 2012.