@unpublished{rechberger13[TUW-217713], author = {Rechberger, Helmut}, title = {{U}rban {M}ining - {W}hy and {H}ow?}, year = {2013}, note = {eingeladen; {V}ortrag: 2nd {F}reiberg {R}esource {T}echnology {S}ymposium, {F}reiberg; 2013-04-17} }