Variations On A Catalan Folksong (Op. 25) were written by John W. Duarte for solo Guitar. They were based on the Spanish folk melody Canco Del Llabre, one of the most popular Catalan folk tunes to have survived to this day.
John W. Duarte (1919-2004) was a British guitarist, composer, and music journalist. Having received a degree in Chemistry, his fascination with the endless possibilities of the Guitar caused him to abandon science in favour of music. Despite having never formally studied music, he is regarded as one of the foremost composers for Guitar of the 20th century.