@article{FAA_1992_26_2_a8,
     author = {M. N. Araslanov and Yu. L. Daletskii},
     title = {Composite logarithm in the class of formal operator power series},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {57--60},
     publisher = {mathdoc},
     volume = {26},
     number = {2},
     year = {1992},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1992_26_2_a8/}
}