No CrossRef data available.
Published online by Cambridge University Press: 12 March 2014
In [2], [3], J. Grassin characterized those classes of sets which are expressible as a Boolean combination of open sets in the Baire topology on the power set of the natural numbers. From this characterization he deduced that if is a Boolean combination of recursive open sets, then the minimum length for any Boolean combination representing can be realized using recursive open sets.