1. P. Armitage (1971 ) Statistical methods in medical research , ch. 7. pp189 -197 . Oxford Blackwell Scientific Publications.
2. P. Armitage (1971 ) Statistical methods in medical research ch. 8, pp.253 -259 Oxford: Blackwell Scientific Publications.
3. Letter to the Editor
4. On the choice of computational unit in statistical analysis
5. Animal Litters as Experimental Units