@article{FPM_2005_11_3_a4,
     author = {O. V. Efimovskaya},
     title = {Factorization of loop algebras over $\mathrm{so}(4)$ and integrable nonlinear differential equations},
     journal = {Fundamentalʹna\^a i prikladna\^a matematika},
     pages = {79--94},
     publisher = {mathdoc},
     volume = {11},
     number = {3},
     year = {2005},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FPM_2005_11_3_a4/}
}