Doc collection is a vital ingredient of case study research. Photograph by Arisa Chattasa. These documents can provide historic context, corroborate evidence from other sources, and provide insights in to the case that might not be apparent from interviews or observations. Remember to cite those sources in an index of https://hbrcasestudysolution04908.webbuzzfeed.com/33872290/the-hbr-case-study-help-diaries