<prompt> Translate the following text to SwahiliThe latter are helpful in retrospective cumulation as a means of obtaining information from the authors that permits an otherwise unusable case study to be included in the aggregation.  <response>: Hii ni muhimu katika mkusanyiko wa nyuma kama njia ya kupata habari kutoka kwa waandishi ambayo inaruhusu utafiti wa kesi usioweza kutumika kuingizwa katika mkusanyiko. 