Paul Keres is one of the greatest correspondence chess players of all times, and this tournament is in he's memorial.
At the first stage, will we have 25 groups with 10 players, and the best 2 of each group advanve.
In the second stage, theres is only 5 groups with 10 players, and the 2 best advance.
Then, in the final stage, only one group with 10 players and the best is the champion.
You have to play 54 games to win. Good look!