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\newblock On relative normalization in orthogonal expression reduction systems.
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\newblock Perpetuality and uniform normalization in orthogonal rewrite systems.
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\newblock CWI, Amsterdam, 1980.

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\newblock {\em Annals of Pure and Applied Logic}, 24:53--188, 1983.

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\newblock Optimal derivations in weak lambda-calculi and in orthogonal term
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\newblock {\em La Strat\'egie Paresseuse}.
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\newblock Higher-order rewrite systems and their confluence.
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\newblock {\em Description Abstraite des Syst\`emes de R\'e\'ecriture}.
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\newblock A stability theorem for rewriting theory.
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