@techreport{plt-tr2010-version-v4.2.4, author = {PLT}, title = {Version: {PLT} Version Checking}, number = {PLT-TR2010-version-v4.2.4}, type = {Reference Manual}, institution = {PLT Scheme Inc.}, month = {January}, year = {2010}, url = {http://download.plt-scheme.org/doc/4.2.4/pdf/version.pdf}, note = {\url{http://plt-scheme.org/techreports/}} }