"You can have that test, but it can't be an exclusive test because of the nature of the patent laws which are to protect new and unknown inventions."

VOA: special.2010.07.16

The isolated country is also under pressure because of United Nations sanctions imposed after Pyongyang conducted a nuclear test a year ago.

VOA: standard.2010.05.03

"They are around and they stand the test of time because they can still raise questions about what we are going through today."

VOA: standard.2010.04.08