1. Coverings of twisted Chevalley groups over commutative rings;Abe;Tokyo Kyoiku Daigaku (A),1977
2. The multiplicators of certain simple groups;Alperin,1966
3. Geometric Algebra;Artin,1957
4. Theory of Lie Groups;Chevalley,1946
5. The Algebraic Theory of Spinors;Chevalley,1954