@unpublished{ChenLua2008,
  author  = {Hua Chen and Zhuangehu Lua},
  title   = {On the holomorphic solution of non-linear totally characteristic equations with several space variables},
  institution = {Institut f{\"u}r Mathematik},
  series    = {Preprint},
  number    = {(1998) 06},
  year    = {2008},
}