title: processing complex aggregate queries over data streams. authors: a dobra , m garofalakis , j gehrke , r rastogi. venue: sigmod conference. year: 2002
title: multiple aggregations over data streams. authors: r zhang , n koudas , bc ooi , d srivastava. venue: proceedings of the 2005 acm sigmod international conference & hellip ; ,. year: 2005.0