Do an "overview" search in TechCat+. Limit to Articles or Peer-Reviewed Articles using the facets on the left of the results list.
Do an in depth search on one of the subject databases. These may be more thoroughly indexed, and will likely have fewer false hits.
Search for case studies in TechCat or a database.
TechCat - Search by keyword and the phrase "case study" in quotation marks
Business Source Complete - Search by keyword and select case study under "Special Limiters...
Proquest Business/ABI Inform - Search by keyword and limit by case study under "Document Type"
Thousands of journal articles, conference proceedings, and other types of periodical literature are identifiable through subscription databases. Many of the articles are available electronically, while others may be found in the print collection or requested through interlibrary loan.
Suggested starting points...