Taxon - Links and literature
de Jong, Y.S.D.M. (ed.): Fauna Europaea 2.4 [http://www.faunaeur.org] [as Ancyla holtzi Friese, 1902]Data retrieved on: 9 March 2012
Ruggiero M. (ed) (2008): World Bee Checklist [http://www.itis.gov/beechecklist.html], ITIS [as Ancyla holtzi Friese, 1902]Data retrieved on: 10 April 2010