Probably any game coolection of his. He has several good books he wrote or cowrote.
Which is the best book to study Anatoly Karpov?

Any ideas? I wanted to understand the strategic games of Karpov.
https://www.ecforum.org.uk/viewtopic.php?t=4527
Is a lengthy thread on books by and about Karpov.
https://www.newinchess.com/media/wysiwyg/product_pdf/7529.pdf
https://web.archive.org/web/20140708102107/http://www.chesscafe.com/text/review795.pdf
https://www.newinchess.com/media/wysiwyg/product_pdf/6078.pdf
https://web.archive.org/web/20140708090609/http://www.chesscafe.com/text/review797.pdf
https://www.newinchess.com/media/wysiwyg/product_pdf/6079.pdf
Any ideas? I wanted to understand the strategic games of Karpov.