@techreport{plt-tr2009-gui-v4.2, author = {Matthew Flatt and Robert Bruce Findler and John Clements}, title = {{GUI}: {PLT} Graphics Toolkit}, number = {PLT-TR2009-gui-v4.2}, type = {Reference Manual}, institution = {PLT Scheme Inc.}, month = {June}, year = {2009}, url = {http://download.plt-scheme.org/doc/4.2/pdf/gui.pdf}, note = {\url{http://plt-scheme.org/techreports/}} }