Improve your Chess Calculation: The Ramesh Chess Course - Volume 1 - Kindle edition by Ramesh, R. B.. Humor & Entertainment Kindle eBooks @ Amazon.com.
The Abstract Image of the Both of Black and White Chess Kings Laying on the Accounting Document and a Calculator, Pen is Placed Ar Stock Photo - Image of kings, graph: 123302004
Improve Your Chess Calculation: A Review - Chess.com
John Napier's Binary Chessboard Calculator - Simplified | Mathematical Association of America