Physical exercise modulates the cellular immune system in patients with rheumatoid arthritis - Lyngberg, K.; Tvede, N.; Halkjær-Kristensen, J.; Andersen, V.; Pedersen, B. K. (Blackwell Publishing Ltd, 1991)
http://dx.doi.org/10.1111/j.1600-0838.1991.tb00291.x
Keywords: WW-YZ; ZX-ZY