Magnetic behaviour of spin 1/2 finite chains intercalated into graphite. Example of the copper chloroaluminate complex M. El Hafidi, G. Chouteau, V. Polo, P. Pernot and R. Vangelisti J. Phys. I France, 3 2 (1993) 371-376 DOI: 10.1051/jp1:1993138