Literature, Sweden. FERDÉN – CENSUS OF SWEDISH MAIL UNTIL 1940. Volumes I–IV. Unnumbered copy identified XXX. Four hardbound cloth-covered volumes in one slipcase. In total 1,800 pages and 1,946 pictures. Close to 40,000 mail items are listed with approx. 60,000 auction results and other references for the period 1872–1940. In addition overviews are presented for foreign mail – partly for the prephilatelic period including for mail sent to e.g. Swedish possessions, German states and other territories; partly for the stamp period 1855–1872. Sold out and sought-after.