@incollection{TUW-120041, author = {Retscher, G{\"u}nther}, title = {Location Based Services und pers{\"o}nliche Navigation}, booktitle = {Angewandte Geod{\"a}sie: Vermessungskunde}, year = {2006}, editor = {Kahmen, Heribert}, pages = {541--552}, publisher = {Walter de Gruyter}, address = {Berlin, New York}, isbn = {3-11-018464-8}, note = {invited} }