St. Agatha - Martyris ecce dies Agathae

Could someone direct me to a copy of the chant notation for "Martyris Ecce Dies Agathae," the hymn of Pope St. Damasus, written in honor of St. Agatha? I found this translation:

Now dawns the feast of Agatha,
The illustrious virgin and martyr;
Christ has espoused her to himself,
And crowns her with a double crown.

Of noble race and beauteous form,
More illustrious still by deeds and by faith,
She sets no value at all on earthly well-being,
But binds to her heart the commands of her Lord.

Stronger by far than her cruel tormentors,
She yielded her fair limbs to the terrible scourgings,
And proved the great fortitude deep in her bosom,
By enduring in her breasts the bitterest of tortures.

To her the dungeon was a place of delight,
And thither came Peter the Shepherd to comfort his lamb.
Thus encouraged and burning with still greater zeal,
She joyfully ran the ever new torments to meet.

The pagan mob fleeing the peril of Etna's fierce flames,
By Agatha's power is effectively aided.
And those who take pride in their title of faithful
From unchastity are also preserved by the saint.

Now that as a bride she shines resplendent in heaven,
May she beg the Lord's mercy on those who are wretched,
And whilst here below we celebrate her feast,
May she be propitious to all who praise her great name.