H. S. K.  Donisthorpe, The guests of British ants: their habits and life-histories. London: George Routledge & Sons, 1927, p. xiii + 244 pp.

C.  O'Toole, ?Ants, bees and wasps (aculeate Hymenoptera)?, A Dipterist's handbook, pp. 157-162, 1978.