Avery, Gene2010-01-252010-01-251958-01-15Avery, G., (1958), "Slotted Clip Board for Viewing Aerial Photos", Minnesota Forestry Notes 63, School of Forestry, University of Minnesota0099-4332https://hdl.handle.net/11299/56716Published as Miscellaneous Journal Paper Series No. 964 of the Minnesota Agricultural Experiment Station.en-USforests and forestryMinnesotaresearchReport