Autor: Patrick Holford. Hyla Cass. TDK862 Páginas: 318 Natural Highs: The healthy way to increase your energy, improve your mood, sharpen your mind, relax and beat stress: Increase Your Energy, Sharpen. Natural and Healthy Mind-altering substances. Piatkus, 2002, 318pp, Tapa blanda. Textos en inglés.