Scaling relationship between the copositive cone and Parrilo's first level approximation. - Peter J. C. Dickinson; Mirjam Dür; Luuk Gijben; Roland Hildebrand (Optim. Lett., 2013)

On the computational complexity of membership problems for the completely positive cone and its dual. - Peter J. C. Dickinson; Luuk Gijben (Comput. Optim. Appl., 2014)