作者:RESEK, RW
作者单位:University of Illinois System; University of Illinois Urbana-Champaign
作者:WILLES, MH
作者单位:University of Pennsylvania
作者:SPRENKLE, CM
作者单位:University of Illinois System; University of Illinois Urbana-Champaign
作者:NICHOLS, A
作者单位:University of South Dakota