1. Paul, D., Yeates, D., & Cadle, J. (2020). Business Analysis (4th ed.). BCS, The Chartered Institute for IT. In Chapter 10, "Making a Business and Financial Case," Section 10.5.2 discusses the evaluation of shortlisted options, emphasizing the need to assess solutions against a range of criteria including both functional fit and non-functional characteristics like usability and support.
2. Sommerville, I. (2016). Software Engineering (10th ed.). Pearson. Chapter 15, "Software Reuse," Section 15.2.2 on "COTS system assessment" explains that the evaluation process involves checking for functionality, assessing performance and usability, and understanding the required support. This confirms the need for a multi-faceted observation.
3. Nielsen, J. (1994). Usability Engineering. Morgan Kaufmann. Chapter 2, "Usability Heuristics," outlines key principles for usability inspection. Principles such as "Help and documentation" (related to Help Routines), "Consistency and standards," and "Aesthetic and minimalist design" (related to Understandability and Clarity) are presented as essential for evaluating a system's user interface.