JOURNAL OF ALGEBRA AND ITS APPLICATIONS, cilt.15, sa.7, 2016 (SCI-Expanded)
Let F-n be a free Lie algebra of finite rank n, n >= 2. We give another proof of the following criterion which is proven by Mikhalev and Zolotykh, using the idea of k-primitivity: An endomorphism of F-n preserving primitivity of elements is an automorphism.