Thank you both, great sources. Huan <div class="gmail_extra"> <div class="gmail_quote">On Wed, Nov 14, 2012 at 9:47 PM, Norbert E. Fuchs <<a href="mailto:fuchs@ifi.uzh.ch" target="_blank">fuchs@ifi.uzh.ch</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="im"> On 14 Nov 2012, at 10:25 , Kaarel Kaljurand <<a href="mailto:kaljurand@gmail.com">kaljurand@gmail.com</a>> wrote: > In the literature you can also find decidable CNLs which at the same > time are subsets of ACE. See e.g. the papers listed on: > > - <a href="http://www.cs.man.ac.uk/~ipratt/" target="_blank">http://www.cs.man.ac.uk/~ipratt/</a> </div>One specifically relevant paper is Pratt-Hartmann, I., Third, A. More fragments of language. Notre Dame Journal of Formal Logic, vol. 47(2), pp. 151—177 (2006) --- nef </blockquote></div> </div>