A leafcutter bee trace fossil from the Middle Eocene of Patagonia, Argentina, and a review of megachilid (Hymenoptera) ichnologyv. 51BLACKWELL PUBLISHING933–941
Sarzetti, L. C., Labandeira, Conrad C., and Genise, J. F. 2008. "A leafcutter bee trace fossil from the Middle Eocene of Patagonia, Argentina, and a review of megachilid (Hymenoptera) ichnology." Palaeontology, 51 933–941.