Do you know who really wrote this?
In GEMA (and BMI) is: Lyrics: Alberto Testa, Music: Tony Renis.
Mina (the singer) says: Renis, Newell, Testa, C. Baltasar (?), Amart (?). These credits are reported both in her releases and in her official site.
Here is the only place where I found a reference to Fabio Testa (presumably Alberto's brother, who might be an alias of Baltasar, or Amart, or both???).