Baker v. Selden
Selden's "Condensed Ledger" allowed someone to conduct double-entry bookkeeping on a single page. The idea of double-entry bookkeeping is generally credited to Luca Pacioli, an Italian mathematician, Franciscan friar, and contemporary of Leonardo de Vinci.
In 1494, Pacioli published Summa de Arithmetica, Geometrica, Proportioni et Proportionalita, the cover of which is displayed to the left. In it, Pacioli described the accounting methods of local merchants, refined them, and produced the first written account of the double-entry system.
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