We give more results on the question of commutativity up to a factor for bounded operators and which has been recently of interest to a number of mathematicians. We also give some generalizations to unbounded operators.
Cite this article
Mohammed Hichem Mortad, Commutativity up to a Factor: More Results and the Unbounded Case. Z. Anal. Anwend. 29 (2010), no. 3, pp. 303–307