[WORLD SCIENTIFIC Proceedings of the Mathematical Legacy of R P Feynman & Proceedings of the Open Systems and Quantum Statistical Mechanics - Lisbon (Portugal) & Santiago (Chile) (3 – 7 June, 7 – 11 January 2002)] Stochastic Analysis and Mathematical Physics - STOCHASTIC OSCILLATORY INTEGRALS: ASYMPTOTICS AND EXACT EXPRESSIONS FOR QUADRATIC PHASE FUNCTION