Chopin: Nocturne No.20 in C sharp minor, Op.posth.; Chopin:Nocturne No.20 In C Sharp Minor,Op.Posth. Nocturne No.20 in C sharp minor, Op.post. Nocturne No.20 in C sharp minor,Op.posth. Chopin: Nocturne in C-sharp minor Op. posth. Nocturne No. 20 in C sharp minor, op. post. Nocturne No.20 in C sharp minor,Op.osth. Nocturne No.20 in C sharp minor Op.posth Nocturne No.20 in C sharp minor,Op.posh 1.Chopin: Nocturne in C-sharp minor Op. posth.