1. Balduf (W. V.), 1962. — Life of carpenter bee,Xylocopa virginica (Linn) (Xylocopidæ, Hymenoptera).Ann. Ent. Soc. Amer.,55, p. 263–271.
2. Kapil (R. P.) andDhaliwal (J. S.). —a. Biology ofXylocopa species. I. Seasonal activity, nesting behaviour and life cycle (in press,J. Res. Pb. Agricultural Univ.).—Kapil (R. P.) b. Biology ofXylocopa species. II. Field activites, flight range and trials on transportation of nests (in press,J. Res. Pb. Agricultural Univ.).
3. Lecomte (J.), 1963. — Le comportement agressif des ouvrières d'Apis mellifica L.Doctoral Thesis, University of Paris, p. 116.
4. Lin (N.), 1964. — Increased parasitic pressure as a major factor in the evolution of social behaviour in Halictine bees.Insectes Sociaux,11, p. 187–192.
5. Lindauer (M.), 1965. —Social behaviour and mutual communication, in thePhysiology of insecta, ed. by Morris Rockstein, p. 123–186.