From the yahoo.com article:
A French museum has found a previously unknown piece of music handwritten by Mozart, a researcher said Thursday. The 18th century melody sketch is missing the harmony and instrumentation but was described as an important find.
Ulrich Leisinger, head of research at the International Mozarteum Foundation in Salzburg, Austria, said there is no doubt that the single sheet was written by the composer.
“This is absolutely new,” Leisinger said in a telephone interview. “We have new music here.”
“His handwriting is absolutely clearly identifiable,” he added. “There’s no doubt that this is an original piece handwritten by Mozart.”
The work, described as the preliminary draft of a musical composition, was found by a library in Nantes in western France as staff were going through its archives. Leisinger says the library contacted his foundation for help authenticating the work.
“It’s a melody sketch so what’s missing is the harmony and the instrumentation but you can make sense out of it,” he said. “The tune is complete. It’s only one part and not the whole score with eight or twelve parts.”
Read the article here.