“Thermal recovery of oxygen-deficient superconducting YBa 2Cu3O7-6 oxides in oxygen ambient”, K. N. Tu, N.-C. Yeh, S. 1. Park, and C. C. Tsuei, Phys. Rev. B 38 , 5118 (1988).
https://journals.aps.org/prb/abstract/10.1103/PhysRevB.38.5118
https://yehgroup.caltech.edu/files/2016/07/PhysRevB.38.5118_115.pdf