1. [Be] Berman, S.: On generators and relations for certain involutory subalgebras of Kac-Moody Lie algebras. Commun. Algebra17 (12), 3165–3185 (1989)
2. [BM] Benkart, G.M., Moody, R.V.: Derivations, central extensions and affine Lie algebras. Algebras Groups and Geom.3, 456–492 (1986)
3. [Bo] Bourbaki, N.: Groupes et algèbres de Lie, Chap. IV, V, VI. Paris: Hermann 1968
4. [Ca] Carter, R.W.: Simple Groups of Lie Type. London: Wiley 1972
5. [Fa] Faulkner, J.R.: Barbilian Planes. Geom. Dedicata30, 125–181 (1989)