SSAA chorus, piano, and cello - Digital Download SKU: OX.9780193570979 Composed by Sarah Quartel. Sheet music. Octavo. 8 pages. Oxford University Press Digital #9780193570979. Published by Oxford University Press Digital (OX.9780193570979). ISBN 9780193570979.For SSAA, piano, and cello. Prologue is the first movement from Sarah Quartel's Snow Angel, an evocative five-movement choral work which is a firm favourite with choirs across the world. The musical language is emotive and pictorial with a haunting and poignant cello line woven throughout the work.