Reviews are a form of static analysis and a fundamental quality assurance activity applicable to any work product created during the software development lifecycle. The primary purpose of a review is to find and remove errors and ambiguities early. Therefore, it is a best practice to perform reviews on critical artifacts such as requirements specifications (to ensure they are clear and correct), source code (to check for defects and adherence to standards), and test plans (to verify coverage and strategy). This proactive approach is highly cost-effective for improving the quality of the final product.

A. Reviews are a primary and essential technique for validating and verifying user requirements specifications to find defects early.

B. Code reviews (a type of static testing) are considered one of the most effective ways to find defects in code.

C. Reviews are highly effective at finding omissions, ambiguities, and errors in test plans, ensuring proper test coverage.

1. IIBA, A Guide to the Business Analysis Body of Knowledge (BABOK Guide), v3, 2015. Section 10.34, "Reviews," describes this as a technique to evaluate a work product. It explicitly lists requirements specifications, designs, source code, and test plans as items that are commonly reviewed.

2. IEEE Std 1028-2008, IEEE Standard for Software Reviews and Audits. This standard provides a comprehensive framework for various types of reviews. Its scope (Section 1.2) covers the review of software products and processes, including specifications, code, and test documentation, throughout the lifecycle.

3. Sommerville, I. (2016). Software Engineering (10th ed.). Pearson. In Chapter 8, "Software Testing," the section on "Verification and validation" explains that software inspections and reviews are static V&V processes applicable to all readable representations of the software, including requirements, design models, and the program source code itself (p. 236-239).