Citation Hunt

The Wikipedia snippet below is not backed by a reliable source. Can you find one?

Click I got this! to go to Wikipedia and fix the snippet, or Next! to see another one. Good luck!

In page Hypnotherapy:

"

Peter Marshall, author of A Handbook of Hypnotherapy, devised the Trance Theory of Mental Illness, which asserts that people suffering from depression, or certain other kinds of neuroses, are already living in a trance. He asserts that this means the hypnotherapist does not need to induce trance, but instead to make them understand this and lead them out of it.[1][citation needed]