Custom numbering with greek alphabet

[Costis]

I want to make a custom numbering list with greek characters
mainly in order to number the appendices of my text automatically.

I want to number them with greek characters
á, â, ã etc.

instead of a, b, c, d...

is there any way to do that?

I use cross references in my main text, and so I would like to be automatic.

Thanks

Costis