Generalised Boolean functions are useful in the design of programmable logic arrays. In this paper a heuristic algorithm suitable to minimise such functions is presented. The algorithm generates an irredundant cover by using a local approach to select generalised prime implicants. A benefit of such a method is that the preliminary generation of the set of all the generalised prime implicants is not required. Experimental results are presented, showing a favourable comparison with an already established minimisation algorithm as far as computing speed is concerned.