Issue No. 04 - July (1983 vol. 9)
W.E. Kluge , Gesellschaft f?r Mathematick und Datenverarbeitung GmbH
In applicative systems, program design is based on elementary constructs of the form apply function to argument(s), also called applications, which are to be recursively inserted into each other. Program evaluation follows a process of meaning-preserving transformations which systematically distributes argument expressions within function expressions and substitutes applications of primitive functions by their values, until a constant expression representing the result of the computation with respect to these transformations is being reached.
W.E. Kluge, H. Schlutter, "Petri Net Models for the Evaluation of Applicative Programs Based on ?-Expressions", IEEE Transactions on Software Engineering, vol. 9, no. , pp. 415-427, July 1983, doi:10.1109/TSE.1983.234778