Existence of superposition bases in countable primitively recursively closed classes (Q1098839)

In an earlier paper [Mat. Zametki 27, No.6, 877-883 (1980; Zbl 0439.03019)] the author proved that the set of all one-place functions in any countable primitively recursively closed class of everywhere defined functions has a countable superposition basis. Here this result is extended to the case of many-place functions, where the method of the above paper [loc. cit.] does not carry over to many-place functions.