In this text we study classical Lie algebras. We prove that a periodisation of such Lie algebras without $\s$-component can be presented as a free graded Lie algebra modulo quadratic relations only. Our approach will be through a Chevalley basis and our method relies on elementary tools only.
Homology, Homotopy and Applications, Vol. 4(2), 2002, pp. 337-355
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