1. J. S. Birman, “An inverse function theorem for free groups,” Proc. Am. Math. Soc. 41, 634–638 (1973).
2. A. F. Krasnikov, “Generators of the group F/[N,N]” [in Russian], Mat. Zametki 24, No. 2, 167–173 (1978); English transl.: Math. Notes 24, No. 2, 591–594 (1978).
3. C. K. Gupta and E. I. Timoshenko, “Generating elements for groups of the form F/R′” [in Russian], Algebra Logika 40, No. 3, 251–261 (2001); English transl.: Algebra Logic 40, No. 3, 137–143 (2001).
4. U. U. Umirbaev, “Partial derivatives and endomorphisms of some relatively free Lie algebras” [in Russian], Sib. Mat. Zh. 34, No. 6, 179–188 (1993); English transl.: Sib. Math. J. 34, No. 6, 1161–1170 (1993).
5. V. V. Talapov, “Relative linear dependence problem for the variety of Lie algebras” [in Russian], Sib. Mat. Zh. 25, No. 6, 182–190 (1984); English transl.: Sib. Math. J. 25, No. 6, 979–985 (1984).