O Antiphonae: Antiphonae Maiores
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 1) O Sapientia

2) O Adonai

3) O Radix Iesse

4) O Clavis David

5) O Oriens

6) O Rex Gentium

7) O Emmanuel

 

For more info, Cf:  http://www.newadvent.org/cathen/11173b.htm