He teamed up with Walter Scheidel, a Stanford classicist and historian, to create a model of population growth and decline based on coin-hoard data gathered over the years.

他与Walter Scheidel合作，Walter Scheidel是斯坦福的一个古典学者与历史学家。他们发明了一个人口增长模型，这个模型基于钱币藏匿的数据，这一工作已进行多年。

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The United States, it is perfect, flawless plate bottom, collected from senior coin collectors. To create a new situation of Chinese coins, with.

美，包浆完美，版底无瑕，征集自资深钱币藏家。开创中国钱币新局面，具有。

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So if you want to create a little order in your everyday handbag, start by getting a good Louis Vuitton bag coin pouch for you to use every day.

所以，如果你想创建一个小为你日常的手提包，开始得到一个好的路易·威登行李硬币袋，为你利用每一天。

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It is believed that a mint worker named Samuel Brown made the coin, managing to change the die in order to create a coin bearing a bogus date.

BBC: Rare Liberty Head nickel sells for $3.1m