Normalization

Hello,

could you give me same indication for the normalization issues which use
phonetics.
For example, can j normalize the character "a with over two dots" in "ae"
or similar.

Exist knowed normalizations or same search in this area?
Where can j search or find it?

Thank you before

Donatella Caridi

Universita' degli studi di Pisa
e-mail:caridi@cli.di.unipi.it