The primary purpose of this paper is to discuss certain sequential procedures for discriminating between two values for the ratio of variance components in a simple one-way classification. In order to clarify the presentation of the three procedures discussed, they will first be applied (in Section 2) to the problem of discrimination between two values for the ratio of variances in two distinct normal populations. The arguments in Section 3 closely parallel those in Section 2, and the form of the two sections has been made as similar as possible, to emphasize this parallelism. Section 4 contains some formulae used in calculating approximate average sampling numbers presented in the earlier sections.
"Sequential Procedures in Certain Component of Variance Problems." Ann. Math. Statist. 25 (2) 357 - 366, June, 1954. https://doi.org/10.1214/aoms/1177728791