@misc{OPUS4-30670,
  title     = {Acquisition of aspect},
  booktitle = {Zentrum f{\"u}r Allgemeine Sprachwissenschaft, Sprachtypologie und Universalienforschung (Berlin): ZAS papers in linguistics ; Vol. 29},
  editor    = {Dagmar Bittner and Natalia Gagarina},
  issn      = {1435-9588},
  url       = {http://www.zas.gwz-berlin.de/198.html},
  series    = {ZAS papers in linguistics : ZASPiL},
  number    = {29},
  type      = {workingpaper},
  pages     = {226},
  year        = {2003},
}