"Rubaiyat of Omar Khayyam (Persian: رباعیات عمر خیام). The Rubáiyát (Arabic: رباعیات) is a collection of poems, originally written in the Persian language and of which there are about a thousand, attributed to the Persian mathematician and astronomer Omar Khayyám (1048 – 1123). "Rubaiyat" (derived from the Arabic root word for 4) means "quatrains": verses of four lines." (summary from Wikipedia.)
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