@inProceedings{Ljunglöf-Peter2005-10789,
title = {A polynomial time extension of parallel multiple context-free grammar},
abstract = {It is already known that parallel multiple context-free grammar
(PMCFG) [1] is an instance of the equivalent formalisms simple literal
movement grammar (sLMG) [2, 3] and range concatenation grammar
(RCG) [4, 5]. In this paper we show that by adding the single operation of
intersection, borrowed from conjunctive grammar [6], PMCFG becomes
equivalent to sLMG and RCG. As a corollary we get that PMCFG with
intersection describe exactly the class of languages recognizable in polynomial
time.},
booktitle = {LACL-05, 5th Conference on Logical Aspects of Computational Linguistics},
author = {Ljunglöf, Peter},
year = {2005},
}