1. K. A. Zhevlakov, “Solvability and nilpotency of Jordan rings,” Algebra i Logika,5, No. 3, 37–58 (1966).
2. E. N. Kuz'min, “On anticommutative algebras satisfying the Engel condition,” Sibirsk. Matem. Zh.,8, No. 5, 1026–1034 (1967).
3. A. I. Shirshov, “On certain nonassociative rings and algebraic algebras,” Matem. Sb.,41, No. 3, 381–394 (1957).
4. I. P. Shestakov, “Finite-dimensional algebras with a null basis,” Algebra i Logika,10, No. 1, 87–99 (1971).
5. A. A. Albert, “A structure theory for Jordan algebras,” Ann. of Math.,48, 546–567 (1947).