Kellis, E., & Baltzopoulos, V. (1999). The effects of the antagonist muscle force on intersegmental loading during isokinetic efforts of the knee extensors. Journal of biomechanics, 32(1), S. 19-25. doi:10.1016/S0021-9290(98)00131-6

Kellis, E., and V. Baltzopoulos. "The Effects of the Antagonist Muscle Force On Intersegmental Loading During Isokinetic Efforts of the Knee Extensors." Journal of Biomechanics 32, no. 1 (1999): S. 19-25.

Kellis, E., and V. Baltzopoulos. "The Effects of the Antagonist Muscle Force On Intersegmental Loading During Isokinetic Efforts of the Knee Extensors." Journal of Biomechanics 32.1 (1999): S. 19-25.