Who are these angels?

And lo, the Angel of the Lord

Qui meditabitur (from Strathclyde Motets II)

O Radiant Dawn (from Strathclyde Motets II)

Lux aeterna (from Strathclyde Motets II)

Os mutorum (from Strathclyde Motets II)

Bring us, O Lord

Canticle of Zachariah (from Strathclyde Motets II)

Benedictus Deus