Pietro Di Gianantonio Furio Honsell Marina Lenisa RPO, Second-Order Contexts, and lambda-Calculus. 334-349 2008 FoSSaCS http://dx.doi.org/10.1007/978-3-540-78499-9_24 conf/fossacs/2008 db/conf/fossacs/fossacs2008.html#GianantonioHL08