A copy of this work was available on the public web and has been preserved in the Wayback Machine. The capture dates from 2008; you can also visit the original URL.
The file type is
Plotkin  has conjectured that there exists an absolutely unorderable combinatory algebra, namely a combinatory algebra which cannot be embedded in another combinatory algebra admitting a non-trivial compatible partial order. In this paper we prove that a wide class of combinatory algebras admits extensions with a non-trivial compatible partial order.doi:10.1093/logcom/13.4.481 fatcat:fn2nyncmcvdt7e3uue2xdic6gu