Models of Wave Supported Clumps in Giant Molecular Clouds
  We present plane-parallel equilibrium models of molecular clumps that are supported by Alfven waves damped by the linear process of ion-neutral friction. We used a WKB approximation to treat the inward propagation of waves and adopted a realistic ionization structure influenced by dissociation and ionization due to photons of external origin. The model clumps are larger and less centrally condensed than those obtained for an assumed ionization structure, used in some previous studies, that is more appropriate for dark regions. 
R. F. Coker, J. G. L. Rae, T. W. Hartquist (University of Leeds, UK)