- document
- Yu, Y. (author), Wardenier, J. (author) report 1997
- document
- Yu, Y. (author), Wardenier, J. (author) report 1996
- document
- Yu, Y. (author), Liu, D.K. (author), Puthli, R.S. (author), Wardenier, J. (author) report 1992
- document
- Yu, Y (author), van Wingerde, A.M. (author), Puthli, R.S. (author), Wardenier, J. (author) report 1991