E.  Ranta and Lundberg, H., ? Food niche analyses of bumblebees: a comparison of three data collecting methods?, Oikos, vol. 36, pp. 12-16, 1981.

E.  Ranta and Lundberg, H., ?Resource utilization by bumblebee queens, workers and males in a subarctic area?, Holarctic Ecology, vol. 4, pp. 145-154, 1981.

E.  Ranta and Lundberg, H., ?Resource partitioning in bumblebees: the significance of differences in proboscis length?, Oikos, vol. 35, pp. 298-302, 1980.

H.  Lundberg and Ranta, E., ?Habitat and food utilization in subarctic bumblebee community?, Oikos, vol. 35, pp. 303-310, 1980.

E.  Ranta, Teräs, I., and Lundberg, H., ?Phenological spread in flowering of bumblebee-pollinated plants?, Annales Botanici Fennici, pp. 229-236, 1981.

E.  Ranta, Lundberg, H., and Teräs, I., ?Patterns of resource utilization in two Fennoscandian bumblebee communities?, Oikos, vol. 36, pp. 1-11, 1981.