New midi files were added on March 22, 2008

Midi files were added.

Prélude No.4 in E minor Op.28-4, Prélude No.5 in D major Op.28-5 and Prélude No.6 in B minor Op.28-6 were added to Chopin - 24 Préludes Op.28 (1/4)

Moreover, "24 Préludes Op.28" became complete because it had added the following three articles.

Chopin - 24 Préludes Op.28 (2/4)

Chopin - 24 Préludes Op.28 (3/4)

Chopin - 24 Préludes Op.28 (4/4)