[NTG-context] prevent hyphenation

Hi. I'm typesetting a text with some citations in nineteenth-century Dutch and French, in which I don't want hyphenation. How can this be done? I now have two macros: \def\stophyph{\pretolerance=15000\tolerance=400} \def\starthyph{\pretolerance=200\tolerance=400} At the beginning of every citation I enter \stophyph{} and at the end \starthyph{}. But the cited words are still hyphenated. Putting single words in a mbox also doesn't help... ;( Tanks in advance, Peter van Kranenburg