coordinates conversion

[Marco Valagussa]

I am a new user for grass and I need help:

I have to import a tiff map in to a raster map with latitude/longitude
projection (with use of r.in.tiff && r.rectify).

For this tiff map i have the coordinate of the upper left vertex
in the `GAUSS BOAGA timezone 1 system' and i need to convert these in
latitude/longitude.
The questions are:
		 - What does `GAUSS BOAGA timezone 1 system' mean ?
		 - How can i convert these in latitude/longitude ?
		 - Where can i get some docs about this ?

thanks! (very much) - marco