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2. A.L. Ambler, D.I. Good, J.C. Browne, W.F. Burger, R.M. Cohen, C.G. Hoch and R.E. Wells, "Gypsy: A Language for Specification and Implementation of Verifiable Programs", Proc. A.C.M. Conference on Language Design for Reliable Software, D.B.Wortman (Ed.) {A.C.M. SIGPLAN Notices, Vol.12, No.3 (March 1977)}, pp.1–10.
3. American National Standards Institute, USA Standard FORTRAN, ANSI X3.9-1966 {Approved March 7, 1966} (A.N.S.I., New York,1966).
4. U.Ammann, "Advantages of the Value Parameter (VP) Over the Constant Parameter (CP)", unpublished memorandum {Translated and augmented by N.Wirth, 5 July 1972}, Institut für Informatik, Eidgenössische Technische Hochschule, Zürich (3 July 1972).
5. U. Ammann, "The Method of Structured Programming Applied to the Development of a Compiler", Proc. International Computing Symposium 1973, A. Günther, B. Levrat and H. Lipps (Eds.), pp.93–99 (North Holland Pub. Co., Amsterdam, 1974).