Residual entanglement with negativity for pure four-qubit quantum states. - David Sena Oliveira; Rubens Viana Ramos (Quantum Inf. Process., 2010)

Entanglement measure for pure six-qubit quantum states. - João Luzeilton de Oliveira; David Sena Oliveira; Rubens Viana Ramos (Quantum Inf. Process., 2012)