Dear all, I'm looking for literature on subframes of a given frame, that is, quotient spaces of a given topological space. The theory of sublocales and nuclei is of course well-developed, but I'm having a hard time finding much about quotient locales, although this topic must have been studied before. Have you got any pointers, preferably about compact regular frames and their collections of compact regular subframes? Best, Chris [For admin and other information see: http://www.mta.ca/~cat-dist/ ]