<ref name="Billen_1990">{{cite journal |first1=J. P. J. |last1=Billen |year=1990 |title=The sting bulb gland in ''Myrmecia'' and ''Nothomyrmecia'' (Hymenoptera: Formicidae): a new exocrine gland in ants |url= |journal=International Journal of Insect Morphology and Embryology |publisher= |volume=19 |issue= |pages=133–139 |doi= }}</ref>