ajtocher wrote:by my calculation copyright in these works would naturally expire on 31 Dec 2045
In the U.S., where CPDL servers are located, copyright lasts 70 years after the death of the composer only for works created after December 31st, 1978, which is obviously impossible as Carlo Rossini died in 1975. Carlo Rossini's works are public domain in the U.S. if they were published before 1923, or if they were published betwwen 1923 and 1964 without an appropriate copyright notice, or if copyright was not renewed through an appropriate procedure after 28 years from first publication. I'm not sure whether Carlo Rossini's publisher had targeted the U.S. as a significant market and therefore took care of the procedures to obtain and maintain the copyright status in the U.S.
Anyway, if you wish to contact the editor of Carlo Rossini's works available on CPDL, you may leave a note on his talk page, or use the function "Email this user" that is available on his user page.
Max