Several years later, researchers discovered the exact cause of pellagra: a lack of the B vitamin known as niacin.

VOA: special.2009.01.27

The Barbary States, as they were known, demanded payment for the release of hostages and safe passage of American ships.

VOA: special.2009.05.27

A medical aid program in Kenya offers hope to women and girls suffering from a condition known as fistula.

VOA: special.2010.08.09

The museum,also known as the Met, was created in eighteen seventy by a group of businessmen, artists and thinkers.

VOA: special.2010.08.04

And in some cases that might lead to more job interviews than a degree from a lesser known college.

VOA: special.2009.12.03

His mother, the only woman, he had ever known told him to read the Bible and read it every day.

VOA: special.2010.05.08

Many students save money by starting their education at a two-year public college, also known as a community college.

VOA: special.2010.04.08

He landed in California. He left a hole so deep that to this day it is known as Death Valley.

VOA: special.2009.11.28

A listener named Maki would like to know if the test known as the TOEIC is popular in the United States.

VOA: special.2010.02.18

Later,he wrote some of the best known songs of the civil rights and anti-Vietnam War protests of the sixties.

VOA: special.2011.06.27

The Cleveland Clinic says the cause of cluster headaches is in a brain area known as a trigeminal-autonomic reflex pathway.

VOA: special.2010.03.30

Some other of his best-known plays include "All My Sons", "A View from the Bridge" and "After the Fall."

VOA: special.2009.11.29

To prevent that from happening, American Secretary of State John Hay proposed what became known as the "Open Door" policy.

VOA: special.2010.07.29

Yet sleep scientist Ying-Hui Fu at the University of California, San Francisco,says little is known about the basic need for sleep.

VOA: special.2009.08.26