IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html
At:
inv pair inv13121111111 1. A : Type
2. B : Type
3. (fg.fg/f,g. <f,g,(x.*),(y.*)>) (AB)(A ~ B)
4. (fga.fga/f,#. #/g,a. <f,g>) (A ~ B)AB 5. f : AB 6. g : BA 7. a1 : x:A. g(f(x)) = x 8. y:B. f(g(y)) = y (x.*) = a1