<ref name="Seifert_2004">{{cite journal |first1=B. |last1=Seifert |year=2004 |title=The "Black Bog Ant" ''Formica picea'' Nylander, 1846 - a species different from ''Formica candida'' Smith, 1878 (Hymenoptera: Formicidae) |url=https://antcat.org/documents/4027/20326.pdf |journal=Myrmecologische Nachrichten |publisher= |volume=6 |issue= |pages=29–38 |doi= }}</ref>