Following the successful books by Ray Long, "Yoga Anatomy 3D: The Key Muscles" and "Yoga Anatomy 3D: The Poses," there are now four additional volumes dedicated to all asanas. The volumes are cross-style yoga and operate on a modular principle. Each volume focuses on a specific group of asanas. The fundamental principle describes the biomechanical and physiological principles and their application in the poses. The individual postures are illustrated with colorful, three-dimensional representations of the skeleton, as well as the key muscles, ligaments, and tendons, and are further explained in a directory of movements and muscles. Volume I covers Vinyasa Flow (a dynamic yoga style) and standing poses. Volume II addresses hip openers and forward bends. Volume III includes backbends and twists.