1. R. Filla and J.O. Palmberg: The Eighth Scandinavian International Conference on Fluid Power Tampere, Finland (2003 ).
2. J. Larsson, P. Krus and J.O. Palmberg. Modelling: Proceedings of The Fifth International Conference on Fluid Power Transmission and Control Hangzhou , China (2001).
3. L.I. Buzdugan, O. Balling and P. Chien: ASME Design Engineering Technical Conferences Las Vegas, USA (1999).
4. J. Larsson and P. Krus: Proceedings of The Seventh Scandinavian International Conference on Fluid Power Linköping, Sweden (2001).
5. S. Blouin, A. Hemami and M. Lipsett: ASCE Journal of Aerospace Engineering Vol. 14(2001), p.102.