Étude Op. 25, No. 11 in A minor, often referred to as the Winter Wind in English, is a solo piano technical study composed by Frédéric Chopin in 1836. It was first published together with all études of Opus 25 in 1837, in France, Germany, and England. The first French edition indicates a common time time signature, but the manuscript and the first German edition both feature cut time. The first four bars that characterize the melody were added just before publication at the advice of Charles A. Hoffmann, a friend. Winter Wind is considered one of the most difficult of Chopin's 24 études.
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