April 27, 2014 is declared a Day of new articles in the Ukrainian section of Wikipedia, the free encyclopedia.The flash mob takes place to commemorate Igor Kostenko, one of the authors of Ukrainian Wikipedia, who died Feb.20 on the Majdan in Kiev. In 2013 Igor was one of those who made a proposal to make this flash mob, and he planned to take part in its organization.
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Source: Wikipedia

Ukrainian Wikipedia announces Open Door Day