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Mark Naimark, a renowned mathematician, collaborated closely with Israel Gelfand, making significant contributions to various fields of mathematics. Their joint work, spanning several decades, resulted in groundbreaking research and the development of influential theories, particularly in the areas of functional analysis, representation theory, and operator algebras. Naimark's expertise complemented Gelfand's, leading to a highly productive and impactful partnership that left a lasting legacy in the mathematical community.