Gurdjieff Practice Book: Inner exercises and sacred dances for the unfolding of consciousnessBruno Martin
Gurdjieff Practice Book 2: Food for the growth of the soul - New exercise suggestions for inner workBruno Martin
Gurdjieff Praxisbuch 2: Nahrung für das Wachstum der Seele - Neue Übungsanregungen für innere ArbeitBruno Martin