IIB Nine-branes
  We calculate the tensions of all half-supersymmetric nine-branes in IIB string theory. In particular, we point out the existence of a solitonic IIB nine-brane. We find that the D9-brane and its duality transformations parametrize a two-dimensional surface in a four-dimensional space. 
Eric A. Bergshoeff, Mees de Roo, Sven F. Kerstan, Tomas Ortin, Fabio   Riccioni