I thank Dominique Gatté to inform me about this publication.
Cambridge, Trinity College
Doxastikon oktaechon Θεαρχίῳ νεύματι for the Dormition of the Theotokos, 15 August (fol. 181v)
XV • Sticherarion complete with variants in the redaction of Ioannes Koukouzeles, hold at the library of the Pantokratorou Monastery on Mount Athos (Menaion ff. 1r-192v, Triodion ff. 193r-256r, Pentekostarion ff. 256r-282r, Oktoechos with prosomoia ff. 282r-297r), f. 297 Kolophon by Gennadios Monachos who announces the donation of the manuscript to him. Additional later hands on the preceding and following pages (SAV 1 has a fully notated variant, fol. 0v prosomeia about Ὄσιε πάτερ, see the corresponding folio of the prosomoia collection in the Oktoechos part).
Notated prosomoia (πρ`) composed over the avtomela πάντας ὑπερβάλλων (ἦχ β᾽) and
ὄσιε πάτερ νϊκητὴς μήδων (πλ α᾽) (fol. 283r)
Replies
The last comment referred to the first picture with the Doxastikon oktaechon Θεαρχίῳ νεύματι (lines 2-4), but I replaced it, because it was not correct.
If you compare Copenhagen and this Sticherarion with the Milanese Sticherarion, unlike the other Sticheraria Athanasios used the phthora nenano two times (at the beginning of the devteros section αἱ δὲ· ὑπέρταται and in the plagios devteros section δὲ προώχοντο·). The scribe of the Copenhagen manuscript did not use any phthora and prefers the mesos devteros as medial signature, so that he might have intended the diatonic devteros echoi. The scribe of this sticherarion uses the medial signature of plagios protos at the beginning of the devteros section which clearly avoids chromaticism within this section, but he "confirms" the use of nenano in the plagios devteros section by a medial signature of this phthora—at a kolon, where the other notators did not write any medial signature. It is a diplomatic version between the two other possible redactions of this doxastikon.
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