The souvenir sheet shows the title pages of several ordinances that governed postal services in Denmark in the 17th, 18th, and 19th centuries. Clockwise from the upper left: Christian IV’s Ordinance on Postmen, 1624; Plague Mandate, 1711; Ordinance on Prohibition of Mail by Means Other than the Post, 1775; and Acts on Postal Articles, 1831.
     All of them except the second are obviously postal laws, but the second deals with the plague. Nearly one-third of the population of Copenhagen died in the plague of 1711. The Plague Mandate regulated public activity in response to the problem. Mail could serve as a vector for the spred of the disease, so regulations were necessary.
     The souvenir sheet was issued to mark the World Philatelic Exhibition in Copenhagen, Denmark in 1987.