@inproceedings{Crossprod13,
  pages = {85--92},
  title = {Satisfiability of cross product terms is complete for real
           nondeterministic polytime Blum-Shub-Smale machines},
  author = {Christian Herrmann and Johanna Sokoli and Martin Ziegler},
  series = {Electronic Proceedings in Theoretical Computer Science},
  volume = {128},
  booktitle = {Proc. 6th Int. Conf. Machines, Computations and Universality},
  year = {2013},
}