- document
- de Winkel, G.D. (author), Verheul, A. (author), de Koning, C.H.M. (author), Puthli, R.S. (author), Wardenier, J. (author), Grotmann, D. (author), Sedlacek, G. (author), Dutta, D. (author), Yeomans, N.F. (author) report 1993
- document
- de Winkel, G.D. (author), de Koning, C.H.M. (author), Puthli, R.S. (author), Wardenier, J. (author), Grotmann, D. (author), Sedlacek, G. (author) report 1992
- document
- de Winkel, G.D. (author), de Koning, C.H.M. (author), Puthli, R.S. (author), Wardenier, J. (author), Grotmann, D. (author), Sedlacek, G. (author) report 1992