- document
- Arbocz, J. (author), Vermeulen, P.G. (author), van Geer, J. (author) report 1988
- document
- Vermeulen, P.G. (author) report 1984
- document
- Elishakoff, I. (author), van Manen, S. (author), Vermeulen, P.G. (author), Arbocz, J. (author) report 1984
- document
- Vermeulen, P.G. (author), Elishakoff, I. (author), van Geer, J. (author) report 1984
- document
- Vermeulen, P.G. (author) report 1983