@article {1139,
	title = { Structure in seven bumblebee communities in eastern Finland in relation to resource availability},
	journal = {Holarctic Ecology},
	volume = {5},
	year = {1982},
	pages = {48-54},
	author = {Ranta, E. and Tiainen, M.}
}
@article {1137,
	title = {Resource utilization by bumblebee queens, workers and males in a subarctic area},
	journal = {Holarctic Ecology},
	volume = {4},
	year = {1981},
	pages = {145-154},
	author = {Ranta, E. and Lundberg, H.}
}
