<ref name="Richter_et_al_2020">{{cite journal |first1=A. |last1=Richter |first2=F. |last2=Hita Garcia |first3=R. A. |last3=Keller |first4=J. |last4=Billen |first5=E. P. |last5=Economo |first6=R. G. |last6=Beutel |year=2020 |title=Comparative analysis of worker head anatomy of ''Formica'' and ''Brachyponera'' (Hymenoptera: Formicidae) |url=https://antcat.org/documents/7956/richter_et__al_2020_asp_formicidae_formica_brachyponera_crania.pdf |journal=Arthropod Systematics and Phylogeny |publisher= |volume=78 |issue= |pages=133–170 |doi=10.26049/ASP78-1-2020-06 }}</ref>