Middendorf, I. (1990). The Perceptible Breath. A Breathing Science. Paderborn, Junfermann-Verlag
Stein, M. (1998). Jung's Map of the Soul. An Introduction. Chicago, Carus Publishing Company
Institute for Breath Education Erika Kemmann, Berlin
www.atemlehre-kemmann.de
The Breath educationalists' and therapists' association
www.bvatem.de
