F. Li, Harmer, P., Fitzgerald, K., Eckstrom, E., Stock, R., Galver, J., Maddalozzo, G. F., and Batya, S. S.,
“Tai chi and postural stability in patients with Parkinson's disease.”,
The New England journal of medicine, vol. 366, no. 6, pp. 511-9, 2012.