See, e.g., Josephus, Wars, 6:423–424, transl., H. St.J. Thackeray et al., Loeb Classical Library (Cambridge, Harvard University Press, 1926–1965), Vol. 3, pp. 498–499; Baruch M. Bokser, The Origins of the Seder (Berkeley: University of California 1984), pp. 24–25 and notes.