1. Aalborg Portland R and D seminar on alkali-silica reaction;ICAAR,1974
2. 2nd ICAAR, Symposium on AAR, preventative measures, Reykjavik, Iceland, 1975
3. 3rd ICAAR, The effects of alkalis on the properties of concrete, Wexham Springs, London 1976.
4. 4th ICAAR, The effects of alkalis in cement and concrete, Purdue University, Indiana, USA, 1978.
5. 5th ICAAR The effects of alkalis in cement and concrete, Cape Town, South Africa, 1981.