TEHRAN (FNA)- An Iranian university professor unveiled a new unknown book claimed to be written by Sa'di Shirazi, a highly revered 13th-century poet, who is known both in and outside Iran for his enticing choice of word, ethical and social teachings and deep expressive poetry.

Ali Asqar Jahangiri, the Iranian collector and professor, said he came across the book, titled Kharestan, at a street vendor's stand when he was a kid and has kept it in his private collection in Iran's Kandelous village.

"Kharestan is adorned with illuminations and contains many beautiful miniatures," he told FNA, adding that "it was transcribed about 300 years ago and the calligrapher who did it has also explained difficult or unfamiliar words."

"The book is written in 16 chapters of both verse and prose which criticize the political and social situation of the time in the form of anecdotes and stories."

Although scholars inside Iran have not confirmed the authenticity of the book, many international researchers from Western universities say the book was written by Sa'di.

"I showed the book to many experts inside Iran such as late historian Iraj Afshar, but they could not confirm its authenticity because there is no text mentioning it or referring to it as a book written by Sa'di," Jahangiri explained, adding that a German scholar and Sa'di expert believes the book belongs to the 13th-century poet.

According to Jahangiri, Kharestan had been stolen from the royal library of Fat'h Ali Shah Qajar and fell into the hands of a family who kept it for a long time before selling it along with their waste papers.

Jahangiri says the style of the book clearly shows that it was written by Sa'di and he did no publicize it because it criticized the rulers of the time.

Jahangiri said he had no intention of sending the book abroad and was planning to publish it in Iran so that everybody can have access to it.

Sa'di is best-known for his Boustan and Golestan which present a peculiar blend of human kindness and cynicism, humor, and resignation in the form of stories and personal anecdotes.

He is also remembered as a great panegyrist and lyricist, the author of a number of masterly general odes portraying human experience, and particular odes collected in Qazaliyat (Sonnets) and Qasa'id (Odes).

Sa'di is known world-wide for one of his aphorisms, which adorns the entrance to the Hall of Nations of the United Nations building in New York;

Of One Essence is the Human Race,
Thusly has Creation put the Base.
One Limb impacted is sufficient,
For all Others to feel the Mace.
The Unconcerned with Others' Plight,
Are but Brutes with Human Face.