TY - JOUR T1 - Preface. JO - REFINE UR - https://www.sciencedirect.com/journal/electronic-notes-in-theoretical-computer-science/vol/137/issue/2 PY - 2009/12/01 AU - Derrick J AU - Boiten EA ED - Derrick J ED - Boiten EA PB - Elsevier VL - 137 SP - 1 EP - 3 Y2 - 2025/11/27 ER -