%0 Journal Article %J Physical Review B %D 2009 %T First-principles study of quantum tunneling from nanostructures: Current in a single-walled carbon nanotube electron source. %A Yaghoobi, P %A Walus, K %A Nojeh, A %N 11 %P 115422/1-115422/7 %V 80 %8 09/2009