"Et besøg i Portugal 1866 6 (Du evighedens gåde)" [Danish title] is number 2249 in the Hans Christian Andersen Center's register of Andersen's literary works, i.e. no. 749 in the category poems (the range 1501 - 2900). BFN 899.
"Et besøg i Portugal 1866 6 (Du evighedens gåde)" [Danish title] was first published 14 January 1866, cf. the bibliographic description (in Danish) in : Digterens danske Værker 1822-1875, number in bibliography: 899:
Paa Nytaarsmorgen! (Du Evighedens Gaade, du Lys for min Forstand).
ISBN: 87-11-11339-1
Show this work in its context: all new Andersen publications from 1866.
Editions
The work was published later (19 November 1868) as a part of Et Besøg i Portugal 1866 [Danish title]. (Number 721. BFN 976. Category/genre: Travelogue).
Later edition: October 2000: Et besøg i Portugal 1866 6 (Du evighedens gåde) (BFN ).