1. 
   Oga
   [Gojoseon] Ohga (오가, 五加) or Five Ministers was a political structure of Gojoseon and Buyeo. Literally, Ohga means five gas because "Oh" means five in Korean. Ohga were composed of Dotga, Gaeda, Soga, Malga and Shinga. Dotga is a minister of east area, Gaega was a minister of west are...
   Found op http://en.wikipedia.org/wiki/Oga_(Gojoseon)
   
   
2. 
   OGA
   OGA is an abbreviation used in the United States to signify Other Government Agency. In government and military parlance it is often used to speak euphemistically of the Central Intelligence Agency, particularly when its operations in a particular area are an open secret. A CIA operative may have a...
   Found op http://en.wikipedia.org/wiki/OGA
   
   

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