This edition of Salve Regina by Pierre Villette is a version of this Marian hymn for SATB a cappella. It's written with lyrics in Latin and should be sung at a slow tempo (52).
The lyrical piece features a long introduction followed by the Soprano solo and a finale. At the end of the solo, the voices alternate between the initial tempo and some slower parts to arrive to the close and finish in harmony.
Pierre Villette (1926-1998) was a French composer of choral and instrumental music. Strongly influenced by Catholicism, his musical heritage ran from Fauré to Messiaen.