Leonardo was a close friend of Italian mathematician and Franciscan friar Luca Pacioli, who wrote "De ludo scacchorum." The chess manual was found in a private library last year.

The manuscript, produced about 1500, contains 48 pages of diagrams, each representing a possible chess scenario to which Pacioli offered his solutions, the BBC reported.

Researchers say they have asked experts in the United States to determine if the drawings are, in fact, Leonardo's work, the British network said.