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2. R. Jacques, M. Reppelin, and L. Seigneurin, European Patent 65, 447 (to Rhône-Poulenc Spécialités Chimiques) [CA 98, 160448d (1983)]
3. French Patent 2, 505, 830 (European Patent 66, 482) [CA 99, 5367d (1983)]
4. French Patent 2, 505, 831 (European Patent 66, 483) [CA 99, 38239s (1983)].
5. F. C. Copp, A. G. Caldwell, and D. Collard, European Patent 56, 465 (to Wellcome Foundation) [CA 97, 216171g (1982)].