The first day covers of the set of United Nations are non-standard, since there were 3 different cancellations used.

• The official First Day Cancellation used on 17 April 1958
• The official National Day Cancellation used on 26 April 1958
• The United Nations official stamp cancellation for postal use

 Since the differences and specificity of these cancellations, three different articles have been created. You can get to them through the menu.