Reference:

Vikberg, V., 1999. Crossocerus assimilis and Bethylus boops, two aculeate wasps new to the fauna of Finland (Hymenoptera, Crabronidae and Bethylidae). Entomologica Fennica, 10(4), 245-246.

URL:

https://journal.fi/entomolfennica/article/view/84031

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