“…Notice that this assumption on t is taken in order to ease the computations, even though the codes C h,t,σ are MRD also for t = 3, 4. When t = 3 the inequivalence with the other known F q n -linear MRD codes such as Gabidulin codes, twisted Gabidulin codes and those in [6,7,10,28,47] has been proved in [3,Section 4]. However when t ∈ {3, 4} the computations of this section become more complicated, since some of the arguments that we are going to use do not work.…”