@techreport{,
TITLE = {Fourth Biennial Report : April 1997 -- April 1999},
EDITOR = {{MPI for Informatics, Max Planck Society}},
LANGUAGE = {eng},
INSTITUTION = {Max-Planck-Institut f{\"u}r Informatik},
ADDRESS = {Saarbr{\"u}cken},
YEAR = {1999},
DATE = {1999},
TYPE = {Biennial Report / Max-Planck-Institut für Informatik},
VOLUME = {4},
}