title: Difficulty in the Fermi-liquid-type theory for the in-plane magnetic anisotropy of untwinned YBa2Cu3O6.85 superconductors.
authors.affiliation: National Key Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China.
authors.forename: Hou-Jun
authors.initials: HJ
authors.lastname: Zhao
authors.forename: Jun
authors.initials: J
authors.lastname: Li