Florin Manea, Bianca Truthe: On Internal Contextual Grammars with Subregular Selection Languages.
222-235
Alexander Meduna, Lukás Vrábel, Petr Zemek: An Infinite Hierarchy of Language Families Resulting from Stateless Pushdown Automata with Limited Pushdown Alphabets.
236-243
Friedrich Otto: Centralized PC Systems of Pushdown Automata versus Multi-head Pushdown Automata.
244-251