The Hammer projection, sometimes called the
Aitoff projection, erroneously, is similar to the Mollweide. But where
the parallels on the Mollweide are parallel to the equator, those on
the Hammer projection curve toward the poles.
The Nicaraguan stamp was issued in 1955 to mark the
50th anniversary of Rotary International. The map is centered on
approximately 85° E.
Another presentation of the Hammer-Aitoff
projection is on the three stamp set issued in 1968 by Samoa to mark
the International Human Rights Year.