Debussy wanted to distance himself from what he considered the emotional excess of the Romantics and instead wanted to write music that, through sound, created an ambience similar to that of the Impressionist painters and Symbolist poets of his day.
All books initially copyrighted in the US from 1964 through 1977 have had their copyrights automatically renewed (by law) and the copyrights are still in force. The initial copyright term was 28 years; the renewal was for 67 more years.
Mandatory deposit for works published in the United States. Although copyright registration is not required, the 1976 Copyright Act establishes a mandatory deposit (also called legal deposit) requirement for works published in the United States. Works first published before March 1, 1989, are subject to mandatory deposit if they were published in the United States with copyright notice.