The Tabaghat Aa'lam Al-Shia (Arabic: طبقات أعلام الشیعة) is a twenty-volume encyclopedia of Shia scholars from the tenth to the twentieth century, written by Aqa Bozorg Tehrani. It is divided into eleven chapters, each dedicated to a century. The name of each chapter was inspired by the number of centuries of the occultation of Mahdi.
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