“…are Fredholm operators with the same index, ind (T : The same approach can be used to extend, to the general PDE right hand sides, the BDIE systems for the mixed problems, unbounded domains, BDIEs of more general scalar PDEs and the systems of PDEs, as well as to the united and localised BDIEs, for which the analysis is now available for the right hand sides only from L 2 (Ω), with smooth coefficient and domain boundary, see [3]- [10], [29], [2], [13], [35], [36].…”