W. F. Wulker 1997: Chironomus esai n. sp. (Diptera: Chironomidae) in lakes and reservoirs of central Fennoscandia. - Entomologica Fennica 8: 171-176.
The paper describes karyotype and larval, pupal and adult morphology of Chironomus esai n. sp., which is an important component in Fennoscandian reservoir lakes.