“…For T = M, M sa , M sal , the category Mod(FD T ) of filtered D-modules on T is quasi-abelian in the sense of [Sch99] and its derived category D + (FD T ) is well-defined. We shall use here the recent results of [SS16] which give an easy description of these derived categories and we construct a right adjoint ρ ! sal to the derived functor Rρ sal * : D + (FD Msa ) − → D + (FD M sal ).…”