@article{VMP_2013_14_1_a13,
     author = {T. A. Angelov},
     title = {On evaluation of codifferentials},
     journal = {Numerical methods and programming},
     pages = {113--122},
     publisher = {mathdoc},
     volume = {14},
     number = {1},
     year = {2013},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMP_2013_14_1_a13/}
}