That could be either Scott Number US 1203 or 1204. Both are worth 40 cents mint and about 15 cents used.
4 cents.
Dag Hammarskjold Middle School was created on 1919-10-12.
U Thant
yes he was a flamer
The Nobel Peace Prize 1961 was awarded to Dag Hammarskjold.
Dag hammarskjold
Dag Hjalmar Agne Carl Hammarskjold won The Nobel Peace Prize in 1961.
The Twentieth Century - 1957 I Remember Dag Hammarskjold 6-1 was released on: USA: 28 October 1962
Dag Hammarskjold
Dag Hammarskjold of Sweden was the UN's Secretary General until his aircraft was sabotaged in the Congo in 1961. He was succeeded by U Thant of Burma.
Dag Hjalmar Agne Carl Hammarskjold (1905-1961)
Scott Numbers 1203 and 1204 This a common US commemorative, but it has a story. There was an error made with the background yellow printed upside down. The post office then printed millions of the error version and sold them to anybody who wanted them. Although the error version was printed in much smaller numbers than the original, it is also very common. Bottom line: don't pay more than 20 cents for either retail. If you have one of the inverts on cover with a cancellation prior to the reprint date, it can be worth a premium.