1. Physics Department; University of Northeast; Av. Libertad 5500 W 3404 AAS Corrientes Argentina
2. CENQUIOR (CSIC); Juan de la Cierva, 3 E-28006 Madrid Spain
3. Instituto de Química Médica (CSIC); Juan de la Cierva, 3 E-28006 Madrid Spain
4. NMR Research Group; University of Oulu; 90014 Oulu Finland