Sorry about that. That is the normal text "T" box. Pick a spot in space, move cursor over top the text box on the screen (green with 6 corner expansion squares). Use your right mouse button, this will open a small menu (contextual menu). From here - select attribute link. Now Catia is goint to just be idle, go back to the 3d model and pick attribute in 3d you want to link to.
This site does not allow pics to be posted, search attribute link to text in the Interactive Drafting book. It will be under the advanced tasks area.
Regards,
Derek