@techreport{BrandtBrandt2009, author = {Andreas Brandt and Manfred Brandt}, title = {Approximations for the second moments of sojourn times in M/GI systems under state-dependent processor sharing}, institution = {ZIB}, address = {Takustr. 7, 14195 Berlin}, number = {09-25}, language = {eng}, year = {2009} }