Low frequency and weakly nonlinear spin transport in ferromagnet/insulator single and double junctionsZheng-Chuan Wang, Qing-Rong Zheng, Gang Su and Bao-Heng ZhaoEur. Phys. J. B, 19 4 (2001) 589-597DOI: https://doi.org/10.1007/s100510170304