Zyczkowski: Genuinely multipartite entangled states, orthogonal arrays and Hadamard matrices.
Karol Zyczkowski, Jagellonian University
A pure quantum state of N subsystems with d levels each is called
k-uniform, if all its reductions to k qudits are maximally mixed.
These states form a natural generalization of N-qudits GHZ states
which belong to the class 1-uniform states.