@techreport{plt-tr2009-teachpack-v4.1.5, author = {PLT}, title = {Teachpacks}, number = {PLT-TR2009-teachpack-v4.1.5}, type = {Reference Manual}, institution = {PLT Scheme Inc.}, month = {March}, year = {2009}, url = {http://download.plt-scheme.org/doc/4.1.5/pdf/teachpack.pdf}, note = {\url{http://plt-scheme.org/techreports/}} }