@unpublished{TUW-183205, author = {Schuh, Harald}, title = {BALkan GEodetic Observing System - a scientific challenge for the Balkan countries (BALGEOS)}, year = {2009}, note = {talk: BALGEOS Fall-Workshop 2009, Skopje, Macedonia; 2009-09-28 -- 2009-09-30} }