S. P. Tregelles, An Introduction to the Critical study and Knowledge of the Holy Scriptures, Samuel Bagster & Sons, London 1856, p. 202.
Bruce M. Metzger, Bart D. Ehrman, The Text of the New Testament: Its Transmission, Corruption, and Restoration, Oxford University Press, 2005, p. 77.
The Greek New Testament, ed. K. Aland, A. Black, C. M. Martini, B. M. Metzger, and A. Wikgren, in cooperation with INTF, United Bible Societies, 3rd edition, (Stuttgart 1983), p. 165.
The Gospel According to John in the Byzantine Tradition (Deutsche Bibelgesellschaft: Stuttgart 2007), p. 7