1. Altmann P., 1980. Software-Entwicklung auf der Grundlage von Gleichungskalkülen. TH Aachen, Dissertation.
2. AmbleR A.L., Good D.I., Browne C., Burger W.F., Cohen R.M., Hoch C.G., Wells R.E., 1977. GYPSY: A Language for Specification and Implementation of Verifiable Programs. Sigplan Notices, vol. 12, no. 3, pp. 1–10.
3. Andreka H., Nemeti I., 1979. Applications of Universal Algebra, Model Theory and Categories in Computer Science ( Survey and Bibliography )., vol. 13.
4. Andreka H., Nemeti I., 1980. Additions to Survey of Applications of Universal Algebra, Model Theory and Categories in Computer Science. Computational Linguistics and Computer Languages, vol. 14.
5. Archibald J.L., 1981. The External Structure: Experience with an Automated Module Interconnection Language. Journal of Systems and Software, vol. 2, pp. 147–157.