In his days, Rav Mar Nachshon Gaon, son of Mar Rav Tzadok Gaon, reigned in Sura from the year 4624 for eight years until 4632. [(Tzed"h) And Sheda"k 37 b wrote from 4400 and died in 4416 (thus according to him he reigned for 16 years), and in Hasa"ch page b he wrote Rav Aharon in Pumbedita and Rav Nachshon in Mata Mechasia received their positions around 4400].