One of the first chess books I ever read was on Paul Keres by Reinfeld.
At CCNY (City College of NY) I discovered chess books found no where else.
Probably because Reinfeld, Horrowitz, and others went there.
Over the years I read books on Keres in Dutch, and German.
I have to imagine a proper study of chess would include Tarrasch, Capablanca,
Botvinnik, and Keres.
I recall the following items although having not read them:
Keres, Paul; Harry Golombek (ed. and trans.). Grandmaster of Chess: The Complete Games of Paul Keres. Arco, New York, 1977.
Varnusz, Egon. Paul Keres' Best Games, Volume 1: Closed Games. Cadogan Chess, London, 1994, ISBN 1-85744-064-1.
The following are probably still available:
Paul Keres: The Road to the Top by Paul Keres (Paperback - May 1997)


Paul Keres: The Quest for Perfection (New American Batsford Chess Library) (New American Batsford Chess Library) by Paul Keres (Paperback - April 1, 1997

Keres' best games of chess, 1931-1948 (Bell's chess books) by Paul Keres

GRANDMASTER OF CHESS THE MIDDLE YEARS OF PAUL KERES by Paul Keres (Hardcover - 1966)

Weiltgeschichte Des Schachs, vol 21: Paul Keres by Paul Keres (Hardcover - 1960) The above is the Schwarz series. A diagram every 5 moves.

Theorie Der Schacheroffnungen : Offene & Halboffene Speile by Paul Keres (Hardcover - 1958)


THE ART OF THE MIDDLE GAME by Paul KERES AND ALEXANDER KOTOV TRANSLATED BY H. GOLOMBEK (Paperback - 1964)

Dreispringerspiel bis Königsgambit: Dreispringerspiel, Vierspringerspiel, Italienische Partie, Zweispringer im Nachzuge, Russische Verteidigung, Wiener ... (Moderne Theorie der Schacheröffnungen) by Paul Keres (Unknown Binding - 1971)
The above has to be the East German Opening Series.

PRACTICAL CHESS ENDINGS by PAUL KERES (Hardcover - 1973)


Keres' Best games of chess, 1931-1940, by Paul Keres (Unknown Binding - 1941
I know the above book. Originally it covered 1931 to 1936 or 37.
Notes by Fine, Reinfeld, Tartakower, Keres, Euwe, and others. A masterpiece.

Keres' best games, 1932-1936 (Fred Reinfeld's limited editions) by Paul Keres (Unknown Binding - 1937)

Grandmaster of Chess : The Complete Games of Paul Keres (Three Volumes in One : The Early Games of Paul Keres, The Middle Years of Paul Keres, The Later Years of Paul Keres) by Paul Keres (Paperback - 1972)

And there are others written in Spanish.