@book {Leps2003, title = {Multivariate analysis of ecological data using CANOCO}, year = {2003}, publisher = {Cambridge University Press}, organization = {Cambridge University Press}, address = {Cambridge}, isbn = {9780521814096}, url = {http://books.google.com/books?hl=en\&lr=\&id=DYfseIcJBc8C\&oi=fnd\&pg=PR9\&dq=Multivariate+Analysis+of+Ecological+Data+using+CANOCO\&ots=9XnOXSeCam\&sig=UcThqV2mODB3kgKxH1uaMSKcljw}, author = {Leps, J. and Smilauer, P. and Lep{\v s}, J and {\v S}milauer, P} }