The phase diagram of the extended anisotropic ferromagnetic-antiferromagnetic Heisenberg chain E. Plekhanov, A. Avella and F. Mancini Eur. Phys. J. B, 77 3 (2010) 381-392 Published online: 22 September 2010 DOI: 10.1140/epjb/e2010-00270-7