2959c81e_ufficient_Mating_Material_Rule__2
[0] Example G [2] 
This example shows a setup where there is enough mating material, but mate is still impossible. Both sides are unable to free their forces, since they can't reach the opponent's pawns. All the mating pieces are blocked, only the kings could move until the end of the Time. So the game is drawn immediately when a position like this occurs. These positions are the so called dead positions.
[E4EC] The insufficient Mating Material Rule
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