1. E. Sandewall: 'Current trends in artificial intelligence,' In W. Schneider & A. Sagvall Hein (Eds.), Computational Linguistics inMedicine, pp.11-17. Amsterdam: North-Holland, 1977.
2. C.N. Mooers: "The next twenty years in information retrieval: some goals and predictions,' Western Joint Computer Conference Proceedings, 1959, 15, pp.81-86.