Satheesh Kumar Kumara Chinnaian. “Event-Driven Billing Infrastructure: Algorithmic Pricing Engines, Stream-Based Metering, and Revenue Analytics for Usage-Based Payment Platforms ”. International Journal of Computer Information Systems and Industrial Management Applications, vol. 18, no. 12s, July 2026, pp. 65-75, doi:10.70917/ijcisim-2026-3878.