Norway – back of the book issues

Norway back of the book issues.

Officials
 File:Nor 1st offi.webp|1926 5ø value. File:Norway offentlig long.A.webp|1934 10ø value. File:Norway traitor official.A.webp|1942 40ø value. File:Norway OS official.A.webp|1951 30ø value. File:Norway off sak vert.A.webp|1969 65ø value. 
 * In 1926, small format stamps with the Norwegian arms and inscribed TJENESTEMARKE. In 1929, a 2 on 5ø surcharge was issued.
 * In 1933, a horizontal format design was issued with an Offentlig sak inscription. The lion has a shaded back leg.
 * In 1934-37, a modified design was released. The design now measures 34x18½ mm and the lion leg has no shading.
 * In 1934-47, a shorter design was issued. A 25 on 20ø surcharge was released in 1949.
 * In 1942-44, the design was changed to an eagle over cross emblem of the collaborationist party. NORGE was added to the inscription.
 * In 1951-52, the arms design was brought back, with O.S. the only inscription.
 * In 1955-74, an upright design was released inscribed OFF. SAK.
 * Beginning in 1975, the design was re-released except with the shield background done in crisscross lines.
 * Officials were no longer used after April 1983 and were invalidated in June 1985.

Postage dues
 File:Norway postage due I.jpg|1889 20ø value. File:Norway postage due II.jpg|1922 10ø value. 
 * In 1889-1920, stamps inscribed NORGE / PORTOMÆRKE.
 * In 1921-23, the inscription was changed to NORGE / PORTOMERKE. "at betale" was changed to "å betale".
 * Postage dues were withdrawn in October 1927.

Returned letter stamps
There are ten types of each value. These are scarce if sound.
 * In 1872, stamps were issued on rose paper inscribed Som / ubesörget / aabnet af / Post-Departe / -mentet.
 * Also in 1872, stamps were issued on green paper inscribed Som / uindlöst / aabnet af / Post-Departe / -mentet. This was reprinted in blue violet and rouletted in 1969.

Returned letter stamps were only used up to 1889.  File:Norway ret letter I.png|"opened by the post office" File:Norway ret letter II.jpg|"undeliverable by the post office" 