Martins-Silva, A., Alves, F., & Gomes-Pereira, J. (1999). Determinant factors in a 200-m butterfly swim as related to the fluctuation in horizontal velocity of the body centre of gravity. Biomechanics and medicine in swimming VIII : Proceedings of the International Symposium on Biomechanics and Medicine in Swimming. University of Jyväskyla, Finland June 28 - July 2, 1998, S. 21-24.

Martins-Silva, A., F. Alves, and J. Gomes-Pereira. "Determinant Factors in a 200-m Butterfly Swim As Related to the Fluctuation in Horizontal Velocity of the Body Centre of Gravity." Biomechanics and Medicine in Swimming VIII : Proceedings of the International Symposium On Biomechanics and Medicine in Swimming. University of Jyväskyla, Finland June 28 - July 2, 1998 1999: S. 21-24.

Martins-Silva, A., F. Alves, and J. Gomes-Pereira. "Determinant Factors in a 200-m Butterfly Swim As Related to the Fluctuation in Horizontal Velocity of the Body Centre of Gravity." Biomechanics and Medicine in Swimming VIII : Proceedings of the International Symposium On Biomechanics and Medicine in Swimming. University of Jyväskyla, Finland June 28 - July 2, 1998 1999: S. 21-24.