Kristian Fauchald's Polychaeta DB
Date of publication is sometimes questioned, but a review was published by Férussac in the December 1826 issue of Bulletin des sciences naturelles et de géologie
, vol. 9, p. 363, proving that the frontispiece date is correct. The hint for 1827 may come from a review by the Académie des Sciences, issued March 1827 and bound with the book.