I.  Mannerkoski, ?[Konowia megapolitana Brauns (Hymenoptera, Xiphydriidae), new provincial record]?, Entomologica Fennica, vol. 2, p. 6, 1991.

M.  Viitasaari, ?Nematus tulunensis Vikberg new to the Finnish fauna (Hymenoptera, Tenthredinidae)?, Entomologica Fennica, vol. 2, p. 4, 1991.

R.  Savolainen, ?Interference by wood ant influences size selection and retrieval rate of prey by Formica fusca.?, Behavioral Ecology and Sociobiology, vol. 28, pp. 1-7, 1991.

R.  Rosengren and Sundström, L., ?The interaction between red wood ants, Cinara aphids and pines. A ghost of mutuliasm past??, in Teoksessa: Huxley, C.R. & Cutler, D.F. (toim.), Ant-plant interactions: 80-91. Oxford University Press, Oxford., 1991.

R.  Rosengren, ?Myrsamhället.?, Sphinx, Ser B, vol. ?, pp. 35-48, 1991.

A.  Pekkarinen and Huldén, L., ?Distribution and phenology of the Ancistrocerus and Symmorphus species in eastern Fennoscandia (Hymenoptera, Eumenidae)?, Entomologica Fennica, vol. 2, pp. 179-189, 1991.

P.  Pamilo, ?Evolution of colony characteristics in social insects. II. Number of reproducing individuals?, American Naturalist, vol. 138, pp.  412-433, 1991.

P.  Pamilo, ? Evolution of colony characters in social insects. I. Sex allocation?, American Naturalist, vol. 137, pp. 83-107, 1991.

P.  Pamilo, ? Life span of queens in the ant Formica exsecta?, Insectes Sociaux, vol. 38, pp. 111-119, 1991.

W.  Fortelius, Fletcher, D. J. C., and Cherix, D., ?Queen recruitment in polygynous and polydomous Formica populations.?, in Teoksessa: Veeresh, G.K., Mallik, B. & Viraktamath, C.A. (toim.), Social insects and the environment: 243-244. Oxford and IBH Publishing Co. New Delhi., 1991.

D.  Cherix, Chautems, D., Fletcher, D. J. C., Fortelius, W., Gris, G., Keller, L., Passera, L., Rosengren, R., Vargo, E. L., and Walther, F., ?Alternative reproductive strategies in Formica lugubris Zett. (Hymenoptera, Formicidae). ?, Ethol. Ecol. Evol., Special Issue , vol. 1, pp. 61-66, 1991.

P.  Punttila, Haila, Y., Niemelä, J., and Pajunen, T., ?Ant communities in fragments of old-growth taiga and managed surroundings?, Annales Zoologici Fennici, vol. 31, pp. 131-144, 1991.

P.  Punttila, Haila, Y., Pajunen, T., and Tukia, H., ?Colonisation of clearcut forests by ants in the southern Finnish taiga: a quantitative survey?, Oikos, vol. 61, pp. 250-262, 1991.

P.  Punttila, Haila, Y., Pajunen, T., and Tukia, H., ?Colonisation of clearcut forests by ants in the southern Finnish taiga: a quantitative survey?, Oikos, vol. 61, pp. 250-262, 1991.

M.  Viitasaari and Zinovjev, A., ?Taxonus zhelochovtsevi sp. n. and Apethymus parallelus (Eversmann, 1847) From the Soviet Far-East (Hymenoptera, Tenthredinidae)?, Entomologica Fennica, vol. 3, pp. 175-178, 1991.

V.  Vikberg and Viitasaari, M., ?Trichiosoma nanae sp. n., a Monophage On Betula nana From Finland (Hymenoptera, Cimbicidae)?, Entomologica Fennica, vol. 2, pp. 67-77, 1991.

R.  Jussila, ?Description of the male of Campodorus hyperboreus (Holmgren, 1855) (Ichneumonidae, Hymenoptera).?, Entomologica Fennica, vol. 2, p. 43, 1991.

R.  Jussila, ?Ichneumonidae (Hymenoptera) new to Finland. I.?, Entomologica Fennica, vol. 2, pp. 37-42, 1991.