Scipio Ferro of Bologna well-nigh thirty years ago discovered this rule and handed it on to Antonio Maria Fior of Venice, whose contest with Niccolo Tartaglia of Brescia gave Niccolo occasion to discover it. He [Tartaglia] gave it to me in response to my entreaties, though withholding the demonstration. Armed with this assistance, I sought out its demonstration in [various] forms. This was very difficult.
Ars Magna (Basel, 1545)
Quinquies exscriptus, maneat tot millibus annis.
I wrote it out five times, may it last the same number of millennia.
The final line of Ars magna.
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