**Acknowledgement**

We are grateful to Prof. S. E. Brown at UCLA for helpful discussions and help with the NMR experiments. We also thank other coauthors J. S. Brooks, A. Kobayashi, and H. Kobayashi for our detailed 77Se-NMR work published in ref. [23].

Field-Induced Superconductors: NMR Studies of λ–(BETS)2FeCl4 19

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