@article{JSFU_2021_14_5_a4,
     author = {Oleg V. Kaptsov},
     title = {Iterations and groups of formal transformations},
     journal = {\v{Z}urnal Sibirskogo federalʹnogo universiteta. Matematika i fizika},
     pages = {584--588},
     publisher = {mathdoc},
     volume = {14},
     number = {5},
     year = {2021},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JSFU_2021_14_5_a4/}
}