If you search FiNDit you will find books which discuss case studies in many disciplines. Search FiNDit for "case studies" AND [your subject]. Example of books might include
Haghirian, P. (2013). Case studies in Asian management. Singapore, SGP: World Scientific. Retrieved from http://site.ebrary.com.
Kerzner, H. (2013). Project management: case studies (4th ed). Somerset, NJ: John Wiley & Sons. Retrieved from http://site.ebrary.com.
Lee, B., Collier, P. M., & Cullen, J. (eds) (2007) Qualitative research in organizations and management an international journal. Volume 2, Number 3, Special issue on case studies. Bradford, GBR: Emerald Group Publishing Ltd
Milosevic, D., Patanakul, P., & Srivannaboon, S. (2011). Case studies in project, program, and organizational project management. Hoboken, NJ: John Wiley & Sons. Retrieved from http://site.ebrary.com.
Use FiNDit search "writing "business case" to find examples of preparing or how to write a business case.
These are examples of two eBooks discussing writing business cases:
Adler, G., & Amann, W. (2011). Case writing for executive education: a survival guide. Charlotte, NC: Information Age Publishing. Retrieved from http://www.ebscohost.com/ebooks
Vega, G. (2014). The case writing workbook : a self-guided workshop. Routledge. Retrieved from http://www.ebscohost.com/ebooks.
