Shifting of the magnetic-resonance peak to lower energy in the superconducting state of underdoped YBa2Cu3O(6.8)P. Bourges, L. P. Regnault, Y. Sidis, J. Bossy, P. Burlet, C. Vettier, J. Y. Henry and M. CouachEurophys. Lett., 38 4 (1997) 313-318DOI: https://doi.org/10.1209/epl/i1997-00244-6