PETEK, Tatjana, 2009, Šemrl, Peter(SV-LJUB) Commutativity preserving maps. (English summary). - Linear Algebra Appl. 429 (2008), no. 5-6, 1051-1070. [online]. 2009. [Accessed 12 April 2025]. Retrieved from: http://www.ams.org/mathscinet/pdf/2433163.pdf