List of FIDE chess world number ones - Wikipedia

rating - Why have engines not increased top rated chess players' Elo? - Chess Stack Exchange

The Sonas Rating Formula – Better than Elo?

What was Bobby Fischer's rating per age from his first chess game to the time he retired? - Quora

Anatoly Yevgenyevich Karpov, World Chess Champion, Grandmaster

Karpov vs Fischer: Who Is More Popular? - EnthuZiastic

Kasparov Thought For 83 MINUTES After Karpov's SHOCKING 9th Move 😱 - Remote Chess Academy

Why has Karpov's chess rating gotten to 2600? - Quora

How did Anatoly Karpov lose so many rating points despite not playing many competitive games over the past decade? - Quora

Karpov: Move by Move by Sam Collins (2015-09-07): : Books

The Complete Games of World Champion Anatoly Karpov: Kevin J. O'Connell, D.N.L. Levy, J.B. Adams: 9780713431407: : Books