Cardiovascular and sympathetic neural responses to handgrip and cold pressor stimuli in humans before, during and after spaceflight, Qi Fu, Benjamin D. Levine, James A. Pawalczyk, Andrew C. Erlt, André Diedrich, William H. Cooke, et. al.
Department of Kinesiology and Integrative Physiology Publications

Influence of microgravity on astronauts' sympathetic and vagal responses to Valsalva's manoeuvre, James F. Cox, Kari U. O. Tahvanainen, Tom A. Kuusela, Benjamin D. Levine, William H. Cooke, Tadaaki Mano, et. al.
Department of Kinesiology and Integrative Physiology Publications