Group schemes of period 2
  We give an explicit construction of the antiequivalence of the category of finite flat commutative group schemes of period 2 defined over the valuation ring of a 2-adic field with algebraically closed residue field. This result extends the earlier author's approach to group schemes of period p>2 from Proceedings of LMS, 101, 2010, 207-259. 
Victor Abrashkin
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