Kolmogorov's ideas in the theory of operations on sets
Vladimir Grigor'evich Kanovei · Russian Mathematical Surveys · 1988
CONTENTS Foreword Introduction § 1. Introduction to the theory of operations on sets § 2. The Kolmogorov hierarchy § 3. The R-transform § 4. Inductive analysis. Indices § 5. R-sets: construction of the hierarchy § 6. The nature of R-sets § 7. Properties of R-sets § 8. Kolmogorov's problem on the lengths of Borel hierarchies Conclusion References