You can here download the original sources used in the book “Postal Stationery of Denmark – The Bi-coloured Issue 1871-1905”. Be aware that many of the files are large (50MB to 120MB) so it takes time to download them. All the files are IN DANISH but in searchable pdf files, and you can download a total of 7,298 pages of original sources from the bi-coloured period – completely free.
The Postal Acts (Postlovene)
UPU Conventions
The Ordinance on the Use of the Posts (Anordning om Benyttelse af Posterne)
Report on The Post Office and its Business (Beretning om Postvæsenet og dets virksomhed)
Foreign Mail Rate List (Udenrigsbrevposttaxten)
Official Announcements (Officielle Meddelelser) 1869-1905
Post Office Statistics (Postvæsenets Statistikker) 1873/74 to 1905/06