Edward W. Hellman, Grapevine Structure and Function http://aggie-horticulture.tamu.edu/faculty/hellman_structure.pdf
grapevine growth stages http://www.grapes.msu.edu/pdf/Growthstages.pdf
UW-Extension Door County IPM Report http://door.uwex.edu/files/2010/10/IPMReport5409.pdf