Griffor, E. R. (1999), Handbook of Computability Theory, Studies in Logic and the Foundations of Mathematics, vol. 140, Elsevier, p. 595, ISBN 9780080533049. 9780080533049
Moret, Bernard M. E. (1998), The Theory of Computation, Addison-Wesley, p. 338, ISBN 9780201258288. 9780201258288
Griffor, E. R. (1999), Handbook of Computability Theory, Studies in Logic and the Foundations of Mathematics, vol. 140, Elsevier, p. 595, ISBN 9780080533049. 9780080533049
Ben-Or, M. (1983), "Lower bounds for algebraic computation trees", Proc. 15th Annu. Symp. Theory of Computing, pp. 80–86, doi:10.1145/800061.808735. /wiki/Doi_(identifier)
Grigoriev, Dima; Vorobjov, Nicolai (1996), "Complexity lower bounds for computation trees with elementary transcendental function gates", Theor. Comput. Sci., 157 (2): 185–214, doi:10.1016/0304-3975(95)00159-X. /wiki/Doi_(identifier)