Co-algebraic structure of the typed lambda-calculus

I have been able to find some references to the co-algebraic structure of the untyped lambda-calculus, (work of Honsell and Lenisa, available at http://citeseer.ist.psu.edu/95166.html and http://portal.acm.org/citation.cfm?id=645892.671579&coll=&dl=ACM&CFID=15151515&CFTOKEN=6184618 ), but my search for a typed analogue has not turned up anything (which I could recognize as being what I was looking for). I found work by various authors (P. Aczel, B. Jacobs, J. Rutten, etc) which seemed 'close', but nothing seemed quite 'right'. I rather suspect that this has already been done and I am simply not using the right terms in my searches - could someone please provide me with some references? Thanks, Jacques