Spin-singlet superconductivity with multiple gaps in PrFeAsO0.89F0.11 K. Matano, Z. A. Ren, X. L. Dong, L. L. Sun, Z. X. Zhao and Guo-qing Zheng EPL, 83 5 (2008) 57001 Published online: 30 July 2008 DOI: 10.1209/0295-5075/83/57001