1. Agresti, A.: Categorical Data Analysis, 3rd edn. Wiley, New Jersey (2013)
2. Asmussen, S., Edwards, D.: Collapsibility and response variables in contingency tables. Biometrika 70, 567–78 (1983)
3. Birch, M.W.: Maximum likelihood in three-way contingency tables. J. R. Statist. Soc. B 25, 220–223 (1963)
4. Birch, M.W.: The detection of partial association, I: the $$2 \times 2$$ case. J. R. Statist. Soc. B 26, 313–324 (1964)
5. Birch, M.W.: The detection of partial association, II: the general case. J. R. Statist. Soc. B 27, 111–124 (1965)