One of these books recommended ending a public recitation of the Little Office with the appropriate Marian Antiphon. This is how Compline always ends, but is optional for the other hours.
You could even pray it by itself.
Here are the words:
Alma Redemptóris Mater, quæ pérvia cæli
Porta manes, et stella maris, succúrre cadénti,
Súrgere qui curat pópulo: tu quæ genuísti,
Natúra miránte, tuum sanctum Genitórem
Virgo prius ac postérius, Gabriélis ab ore
Sumens illud Ave, peccatórum miserére.
Kind mother of the Redeemer, who remain the open gate of heaven and the star of the sea:
help your falling people who want to rise, you who bore your holy Parent, while nature marveled:
a Virgin before and after, receiving that ‘Ave’ from Gabriel’s mouth, have mercy on [us] sinners.
You will notice there are two different collects for this Antiphon - one for Advent and one for Christmas. I have sung the one for Christmas here.
Solemn Alma Redemptoris for Christmastide