"Hayashi Reiki Manual" by Frank Petter, Tadao Yamaguchi, Chujiro Hayashi

"The Hayashi Reiki Manual: Traditional Japanese Healing Techniques"

"Light On The Origins of Reiki" by Tadao Yamaguchi

"Light on the Origins of Reiki: A Handbook for Practicing the Original Reiki of Usui and Hayashi"

"Reiki And Japan" by Masaki Nishina

"Reiki and Japan: A Cultural View of Western and Japanese Reiki"

"This Is Reiki" By Frank Arjava Petter

"This is Reiki: Transformation of Body, Mind and Soul from the Origins to the Practice"