Before revision: Volpano, Smith and Irvine were the first to prove a security type system sound using the notion of non-interference for a deterministic programming language with a standard (non-instrumented) semantics .
After revision: Volpano, Smith and Irvine were the first to prove a security type system soundness ofimperativeusing the notion of non-interference for a deterministic programming language with a standard (non-instrumented) semantics .