The Greek fragment of St Mark's Gospel known as Wd, taken from the binding of B.8.5 and now preserved between sheets of glass in a wooden frame. It is in sloping uncials of cent. ix.
For a complete transcript and photographic facsimile, see J. Rendel Harris, The Diatessaron of Tatian, Cambridge, 1890, pp. 43, 62 sqq.
Duplacy, J., 'La Provenance Athonite des manuscrits Grecs lἓguἓs par R. Bentley ώ Trinity College, Cambridge, et en particulier de l'oncial O131 du nouveau testament', in Studies in the History and Text of the New Testament in honor of Kenneth Willis Clark Ph.D., ed. Daniels, B. L., and M. J. Suggs, Studies and Documents 29 (Salt Lake City, UT, 1967), 113-26
Rendel Harris, J.,The Diatessaron of Tatian, Cambridge (1890), pp. 43, 62 sqq.