E.  Ranta and Tiainen, M., ? Structure in seven bumblebee communities in eastern Finland in relation to resource availability?, Holarctic Ecology, vol. 5, pp. 48-54, 1982.

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.

J.  Silvola, ?Respiration and energetics of the bumblebee Bombus terrestris queen?, Holarctic Ecology, vol. 7, pp. 177-181, 1984.