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Endgame Books for Tournament Players

Most important is not in the list: 100 endgame you must know of Jesus de la villa
I would add Practical Chess Endings by Paul Keres (1973) ISBN 0-7134-4210-7. It was the first endgame book I used when learning the game (even thought it was published before I was born) and I still find it really useful to dip in and out of.
Wait, what tournament opponent? You haven't played a FIDE game since 2010-ish
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For learning Pawn endgames, "The final countdown" by van Riemsdijk and Hajenius, which I liked a lot, in combination with Lazlo Polgar's Endgame book are nice ressources.
On rook endgames of course the Smyslov Levenfish
Besides, I went through several DVDs of Müller's monumental endgame series and read his 3 books.
Nunn's "Endgame Challenge" and Lutz's "Endgame Secrets" also worth reading