World Polychaeta Database (WPolyD)
Published in October 1857. Publication has a footnote stating the following: ''
De særskilte Aftryk af Afhandlingerne indtil Side 199 vare omdelte til Forfatterne inden October 1857. Det samlede Hefte færdigt til Omdeling 26de Februar 1858'' (which translates approximately as: ''The treatises until page 199 were distributed to the authors in October 1857. The total volume was ready for distribution the 26th February 1858.'')