1. APU Occasional Paper No. 4, APU Science Team,1986
2. Beyer, K. and Reich, J. L.Proceedings of the Fourth International Conference of gasat. Ann Arbor. Vol. 1, University of Michigan.
3. Beyer, K., Blegaa, S. and Vedelsby, M.Proceedings of the Third International Conference of GASAT. Centre for Educational Studies, University of London.
4. Blegaa, S. and Reich, J.Proceedings of the Fourth International Conference of GASAT. Vol. 2, Ann Arbor: University of Michigan.
5. Brynhi, E. and Lie, S.Proceedings of the Third International Conference of GASAT. Centre for Educational Studies, University of London.