This may be a limited edition printing, which if so, would have the notations on the very back pages. This can factor into the value, if it is. As well, the value is also based on who the illustrator is - is there just one or several? The average price of copies of the Rubaiyat published at the beginning of the 20th century if $100. If done by a desirable illustrator with a collector following, this can sell for up to $400 on today's market.
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