- document
- Havenbedrijf Rotterdam (author) report 1990
- document
- Drewry Shipping Consultants (author) public lecture 1988
- document
- Drewry Shipping Consultants (author) report 1988
- document
- Nederlands Maritiem Instituut (author) report 1977
- document
- Nederlands Maritiem Instituut (author) report 1976