Ryo Ishigaki Kentaro Kikuchi Tree-Sequent Methods for Subintuitionistic Predicate Logics. 149-164 2007 conf/tableaux/2007 TABLEAUX http://dx.doi.org/10.1007/978-3-540-73099-6_13 db/conf/tableaux/tableaux2007.html#IshigakiK07