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2. Chem. Abstr., 67, 90824g (1967).
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4. Chem. Abstr., 68, 78303z (1968).
5. Badische Anilin- und Soda-Fabrik A.-G., French Demande 2,001,700, 26 Sep. 1969; German Appl. 10 Feb. 1968;