US4,343,993 [1] Priority number(s): CH19790008486 19790920, family patents are also published as: EP0027517 (A1) EP0027517 (B1), and CH643397 (A5) [2].
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US4,343,993 [1] Priority number(s): CH19790008486 19790920, family patents are also published as: EP0027517 (A1) EP0027517 (B1), and CH643397 (A5) [2].