1. STOCHASTIC OPTIMIZATION OF QUERYING DISTRIBUTED DATABASES III. EVOLUTIONARY METHOD VERSUS CONSTRUCTIVE METHOD. Authors: D. DUMITRESCU, V. VARGA.2. STOCHASTIC OPTIMIZATION OF QUERYING DISTRIBUTED DATABASES I. THEORY OF FOUR RELATIONS JOIN. Authors: D. DUMITRESCU, V. VARGA.3. STOCHASTIC OPTIMIZATION OF QUERYING DISTRIBUTED DATABASES II. SOLVING STOCHASTIC OPTIMIZATION. Authors: D. DUMITRESCU, V. VARGA.