Victorinus of Pettau, On the Creation of the World (twelve angels)
To speak by the twelve-fold number, as I recalled above: light and night are divided two ways by twelve hours, and by these hours months and years and seasons and ages are computed. Therefore without doubt twelve angels of the day and twelve angels of the night have been appointed, according of course to the number of hours. For these are the twenty-four witnesses of days and nights (Rev. 4:4) who sit before God's throne, having golden crowns on their heads, whom in the Apocalypse of John the apostle and evangelist he calls elders, because they are older than both other angels and humans.
Latin
Duodenario numero dicere ut supra memoravi, per duodenas horas bifarie divisus est lucis et noctis, per has namque horas, menses et anni et tempora et saecula computantur. Constituta sunt itaque sine dubio autem diei angeli duodecim, noctis angeli duodecim, pro numero scilicet horarum. Hi sunt namque XXIIII testes dierum et noctium (Apoc., IV, 4), qui sedent ante thronum Dei, coronas aureas in capitibus suis habentes, quos in Apocalypsis Joannis apostoli et evangelistae seniores vocat, idcirco quia seniores sunt et aliis angelis et hominibus.