The grouping was first introduced by Caspar RenΓ© Gregory, who assigned papyri texts the Blackletter character π followed by a superscript number.
[2] Before 1900, only 9 papyri manuscripts were known, and only one had been cited in a critical apparatus (π11 by Constantin von Tischendorf).
[3] The discoveries of the twentieth century brought about the earliest known New Testament manuscript fragments.
Among the most important are the Chester Beatty Papyri: π45, which contains the Gospels and Acts; π46, which contains the Pauline epistles; and π47, which contains the Book of Revelation.
[7] These early manuscripts are more complete, allowing scholars to better examine their textual character.