This paper, "Time, Clocks, and the Ordering of Events in a Distributed System," explores the challenges of defining and managing time in distributed systems. It introduces the concept of a "happened before" relation to partially order events and presents an algorithm for creating a consistent total ordering using logical clocks. The paper then extends this to physical clocks, analyzing synchronization and error bounds to prevent anomalous behavior arising from discrepancies between perceived and actual event orderings. The second paper, "Shallow Binding in Lisp 1.5," focuses on efficient variable access in the Lisp 1.5 programming language. It proposes a "rerooting" method for environment tree transformations to achieve shallow binding, allowing for context switching and concurrent processes within the same environment structure, all while maintaining program semantics. The method enhances efficiency without altering a program's meaning.

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