A study of Paul Keres is probably mandated for any player.
An old book no longer available, only found in the City College of NY was
Paul Keres best games 1934-37 with notes by
Keres, Reinfeld, Fine, Tartakower, Euwe, Grob and others.
I noticed Weldtgeschichte des Schachs Vol. 21 Keres , 1960 has notes which are
are the same as Road to the Top.
Road to the Top can be a teaching tool as well as enjoyment.
Keres tells you what he was thinking.
In my PGN file of Keres, I added note to 2068+ games.
Including 2 analysis boards, 1 game not played by Keres but analysed by Keres.
Note that the online downloads contain errors. I have 2068 games because I eliminated
300 games as being errors, or never played by Keres.
THe project is not completed as yet.
For tactics in the Middle Game this is the book to get.