Kotov and Silman should surely be there, as well as Nimzo, in my opinion.
Top ten chess AUTHORS of all time ?

Oh forgive me I surely forgot about Fred Rienfeld I'm sure he'll find his place up there since he's my idol. In terms of openings I'd give John Watson a shout. Lars Bo Hansen is a personal fav of ine but not sure if he's top ten material or not.

In Pawn Power in Chess, Kmoch writes at a different level of granularity about pawn play than Soltis does in Pawn Power Chess. I think they are complimentary. Pachmann at an even different level of granularity about pawn play in Complete Chess Strategy.
I did just go through "Think..." and I like Kotov too.
I guess I'm selecting authors based on single books. Didn't like their other works as much.
RIP Steve Jobs

Soltis (for how to choose chess move), Evans (10most common chess mistakes) and Fine (middlegame in chess)
can't name any author anymore cause that's only the books i've ever read.. to think you're asking for top 10, i can name (and vote) for only 3..

I think I could name a dozen. here's my list, in no particular order.
1. Tarrasch took Steinitz's ideas and made them available to a wide public.
2/3. The hypermoderns: Nimzovich for My System and Chess Praxis and Richard Reti for Masters of the Chessboard and New Ideas in Chess.
4. Alekhine wrote several great books: New York 1924 and his two My Best Games collections.
5. Max Euwe for his Master versus Amateur and his two volumes on the middlegame.
6. Botvinnik for his game collections. He is called the patriarch because his ideas were so widely influential in Russia.
7. Kotov for several books but mainly for Think Like a Grandmaster.
8. Bronstein for 300 Open Games and Zurich 1953, the Chess Struggle in Action.
9. Bobby Fischer didn't write anywhere near enough but I think his My Sixty Memorable Games is a great book.
10. Kasparov for numerous great books.
11. Paul Keres for his Two volume Best Games collections
12. Frank Marshall for his Best Games collection
Hans Kmoch for Pawn Power in Chess deserves honorable mention but his penchant for weird terminology keeps him out of the top dozen. Pachman is another I would give honrable mention to.
I am leaving out the great writers who popularized chess for the masses, guys like Chernev, Horowitz, Reinfeld and Silman. I'd also mention George Mason - his Chess Handbook was the most widely popular chess book of the 19th century.
I'm also leaving out guys from the last thirty years, except for Kasparov, who must be included. Their books haven't yet withstood the test of time.
Nimzowitsch (My System, Chess Praxis, Die Blockade, Carlsbad 1929)
Tarrasch (The Game of Chess, 300 Games of Chess)
Euwe (Middlegame I and II, Judgment and Planning in Chess, A Guide to Chess Endings, Chess Master vs. Chess Amateur)
Dvoretsky (Secrets of Chess Training, Positional Play, Opening Preparation, Endgame Technique, Attack and Defense, Dvoretsky's Endgame Manual, Dvoretsky's Analytical Manual, etc.)
Kotov (Think Like a Grandmaster, Play Like a Grandmaster, Grandmaster at Work, Alexander Alekhine)
Tal (Life and Games of Mikhail Tal, Tal-Botvinnik 1960, Attack with Mikhail Tal)
Bronstein (Zurich 1953, The Sorcerer's Apprentice, 300 Open Games)
Kasparov (The Test of Time, On My Great Predecessors I to V)
Shereshevsky (Endgame Strategy, Mastering the Endgame Vols. 1 and 2)
Znosko-Borovsky (The Art of Chess Combination, How to Play the Chess Endings, How Not to Play Chess, The Middle Game in Chess, How to Play the Chess Openings)
Authors like Keene, Soltis, and Reinfeld are too uneven for my taste.
I was also tempted to add Suetin, but even though I like his books (Three Steps to Chess Mastery, A Contemporary Approach to the Middlegame), I don't think he is required reading.
I only chose authors who had written multiple classic books. That's why Fischer, for example, isn't there.
I don't like the multi-step plans in his annotations, but I guess I have to include Alekhine (My Best Games 1908-1924, 1924-1937, 1937-1945, New York 1924)
My top 3
1. Dvoretsky (undisputed for me)
2. Euwe (he learned his country play chess)
3. E. Mednis (Practical Rook Endings to cite 1 of his 26 books)
Roundig out the rest: Nimzowitsch, Bronstein, Donner (more for his writing style), Suetin, ...

is there really this long list of useful books? and should we beginners be studying those to at least compete at 2000+ ratings here or to any other correspondence chess site?
i'm familiar of some books you mention (some i even have e-book of) but i haven't taken time to read them yet..
but i really want to read the book my system by nimzo, problem is the e-books i'm seeing (my system) are all russian.. unrelated to the topic but do you know any site that offers free e-book of it in english language? TIA..
cheers..

I think I could name a dozen. here's my list, in no particular order.
1. Tarrasch took Steinitz's ideas and made them available to a wide public.
2/3. The hypermoderns: Nimzovich for My System and Chess Praxis and Richard Reti for Masters of the Chessboard and New Ideas in Chess.
4. Alekhine wrote several great books: New York 1924 and his two My Best Games collections.
5. Max Euwe for his Master versus Amateur and his two volumes on the middlegame.
6. Botvinnik for his game collections. He is called the patriarch because his ideas were so widely influential in Russia.
7. Kotov for several books but mainly for Think Like a Grandmaster.
8. Bronstein for 300 Open Games and Zurich 1953, the Chess Struggle in Action.
9. Bobby Fischer didn't write anywhere near enough but I think his My Sixty Memorable Games is a great book.
10. Kasparov for numerous great books.
11. Paul Keres for his Two volume Best Games collections
12. Frank Marshall for his Best Games collection
Hans Kmoch for Pawn Power in Chess deserves honorable mention but his penchant for weird terminology keeps him out of the top dozen. Pachman is another I would give honrable mention to.
I am leaving out the great writers who popularized chess for the masses, guys like Chernev, Horowitz, Reinfeld and Silman. I'd also mention George Mason - his Chess Handbook was the most widely popular chess book of the 19th century.
I'm also leaving out guys from the last thirty years, except for Kasparov, who must be included. Their books haven't yet withstood the test of time.
George Mason---never heard of the guy !
This is a major topic which should be more easier to figure out so who do you think it is ? Although I know he's not number 1 I think GM Raymond Keene deserves a place in the top ten spot.