Vasilev, I. 1987 ("1984"). The ants (Formicidae, Hymenoptera) from the valley of the River Racene. [In Bulgarian.]. Godishnik na Sofiiskiya Universitet "Kliment Okhridski". Biologicheski Fakultet. Kniga 1. Zoologiya 78:74-79.

Notes: Date signed for printing.