Kitab al-Kafi
It is a major secondary source of hadiths, which elaborates on hadith drawn from primary sources compiled centuries earlier such as "Kitab al-Kafi" and "Man la yahduruh al-Faqih". Most of the primary Shia hadith collections are from the 10th and 11th centuries CE, and the secondary ones are either from the late Mongol (14th century) or Safavid era (16th-17th centuries).