The development of an object with constant value which everyone is willing to trade for their goods or services.
The development of an object with constant value which everyone is willing to trade for their goods or services.
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*[[Accounting]] – [[Denise Schmandt-Besserat]] described the first uses of clay tokens and bullae for keeping track of income and expenses.<ref>http://www.utexas.edu/cola/centers/lrc/numerals/dsb/dsb1.html.</ref>
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*[[Accounting]] – [[Denise Schmandt-Besserat]] described the first uses of clay tokens and bullae for keeping track of income and expenses.<ref>https://www.utexas.edu/cola/centers/lrc/numerals/dsb/dsb1.html.</ref>