2007
- Keulen, W. van, Meetonnauwkeurigheden bij geluidmetingen aan stille wegdekken, in Nederland Akoestisch Genootschap. 2007: Utrecht.
- Keulen, W. van, Psychophysics and Silent Roads: an Interesting Combination, invited paper, in INTER-NOISE 2007 – 36th International Congress and Exposition on Noise Control Engineering. 2007: Istanbul.
- Keulen, W. van, Stille wegdekken, regelgeving en bestekken, in KWS Symposium Stil en duurzaam…. Duurzaam stil? 2007.
- Keulen, W. van, New Technique for Silencing Existing Concrete Roads, invited paper, in AFCM Concrete Road Symposium. 2007: Kuala Lumpur.
- Keulen, W. van, Traffic Noise reduction, invited paper. 2007, Dutch Serbian Business Counsel: Belgrade.