A Priestley Sum of Finite Trees is Acyclic.

Richard N. Ball Ales Pultr Jirí Sichler A Priestley Sum of Finite Trees is Acyclic. 735-748 2008 16 Applied Categorical Structures 6 http://dx.doi.org/10.1007/s10485-007-9118-z db/journals/acs/acs16.html#BallPS08