Baku, January 16, AZERTAC The Estonian national postal service (Omniva) has issued a postage stamp marking the “Year of Heydar Aliyev”, the Embassy of Azerbaijan in Tallinn told AZERTAC.The postage stamps, which read “Haidar Alijevi aasta – 100” (Year of Heydar Aliyev - 100) in Estonian language, has officially been put into circulation in Estonia.