1. ' A restatement of the problem of learning.' Brit;Adams;J. Psychol,1931
2. ' Psychologische Beobachtungen an einigen Jungvögeln der Gattungen Stercorarius, Larus u;Ahlqtjist;Sterna.' Acta Soc. Fauna Flora Fenn.,1937
3. Akhmeteli , M. 1941 ' Imitation in pigeons.' Trans. Beritashvili Physiol. Inst 345 365
4. ' Analytical studies of group behaviour in birds;Allee;Wilson Bull.,1936