Racks, Leibniz algebras and Yetter-Drinfel'd modules
  A Hopf algebra object in Loday and Pirashvili's category of linear maps entails an ordinary Hopf algebra and a Yetter-Drinfel'd module. We equip the latter with a structure of a braided Leibniz algebra. This provides a unified framework for examples of racks in the category of coalgebras discussed recently by Carter, Crans, Elhamdadi and Saito. 
Ulrich Kraehmer and Friedrich Wagemann
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