On the dimensions of commutative subalgebras and subgroups of nilpotent   algebras and Lie groups of class 2
  We obtain the functions that bound the dimensions of finite dimensional nilpotent associative or Lie algebras of class 2 over an algebraically closed field in terms of the dimensions of their commutative subalgebras. As a result, we also compute a similar function for complex nilpotent Lie groups of class 2. 
Maria V. Milentyeva
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