Flag of Belgium
This is the national flag of Belgium, according to the Official Guide to Belgian Protocol. It has a 13:15 aspect ratio, though it is rarely seen in this ratio.

Its colours are defined as Pantone black, Pantone yellow 115, and Pantone red 032; also given as CMYK 0,0,0,100; 0,8.5,79,0; and 0,94,87,0.
Van den Bussche, E., Chief of Protocol, Belgian Federal Department of the Interior (2008)       Noble Belgique, ô Mère chérie - LE PROTOCOLE EN BELGIQUE (PROTOCOL IN BELGIUM), Heule:  Editions UGA  ISBN:  9789067689359.
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