A simple 4 page peer review checklist for requirements. This check list is useful for most commercial projects, performing peer reviews. The items that are checked include, clarity, consistency, external interfaces and our software testing directory favorite, testability. This list also contains guidance, for example GUIDANCE: A requirements specification should address such elements as control flow, data transformations, design constraints, and user interface. 

This article for Dr Jody Paul covers walkthrough’s in general, including specification, design, code and test. Not only does it give a good overview of the subject it also presents many useful ideas including check lists and planning.

A formal paper, from the Dept. of Science at the University of Hagen, on validating user requirements by mapping Use Cases to Classes and Operations of an Object-Oriented model. Although this paper has a formal style it does convey the business scenario walkthrough aspect of Validation and references the two most popular UML models, namely Use Cases and Class diagrams.