David Beard Murugappan Palaniappan Alan Humm David Banks Anil Nair Yen-Ping Shan A Visual Calendar for Scheduling Group Meetings. 279-290 1990 CSCW http://doi.acm.org/10.1145/99332.99361 db/conf/cscw/cscw1990.html#BeardPHBNS90