Akimenko, A., Bobba, F., Giubileo, F., Gudimenko, V., Piano, S., & Cucolo, A. (2010). Evidence of a s-wave subdominant order parameter in YBa2Cu3O7-d from break-junction tunneling spectra. ФІЗИКА НИЗЬКИХ ТЕМПЕРАТУР, 36(2), 212–216. https://doi.org/10.1063/1.3319499