Average-Case Complexity Theory of Approximation Problems - Birgit Schelm (Electron. Colloquium Comput. Complex., 2003)

Average case approximability of optimisation problems. - Birgit Schelm (2004)

Average-Case Computations - Comparing AvgP, HP, and Nearly-P. - Arfst Nickelsen; Birgit Schelm (CCC, 2005)

Average-Case Non-Approximability of Optimisation Problems. - Birgit Schelm (Theory Comput. Syst., 2007)