Cluster headaches occur in cycles: sufferers can experience several headaches a day for weeks or even months on end.

VOA: standard.2009.12.17

For Petru Russo, the headaches can occur up to 10 times a day.

VOA: standard.2009.12.17

The challenger contends that ballots marked for Mr.Karzai are arriving from districts where voting did not occur and turnout is being reported as high as 40 percent in areas where only 10 percent of voters cast ballots.

VOA: standard.2009.08.23

The agency notes cultural differences, views and attitudes toward suicide influence whether people will attempt suicide and whether suicides will be accurately reported The WHO report says most suicides in occur in Asia, which accounts for up to But it reports Eastern European countries have the highest rates of suicide.

VOA: standard.2009.09.10