Orthorhombic distortions may reconcile all the experimental data on YBCO
  A lot of controversy appeared recently in measurements of different properties of High-$T_c$-superconductor YBCO. A part of data supports d-wave hypothesis whereas other one contradicts it. We suggest to reconcile visibly controversial experimental data by an assumption that orthorombicity is not small for electronic properties of YBCO, and naturally mixes s- and d-pairing. We examine available experiments to find a proportion of such a mixture. We find in particular that the reconcilation is plausible if the Fermi-surface in YBCO is square-shaped. 
V.L.Pokrovsky