J. Friedrich, S. Scheifele, A. Verl, and A. Lechler. Procedia \CIRP\, (2015)9th \CIRP\ Conference on Intelligent Computation in Manufacturing Engineering - \CIRP\ \ICME\ '14.
J. Friedrich, and A. Verl. Proceedings of the International Conference on Advanced Manufacturing Engineering and Technologies NEWTECH 2013, page 117-126. (2013)