@article{MZM_2021_109_4_a11,
     author = {A. S. Semchankau},
     title = {On {Differences} of {Multiplicative} {Functions} and {Solutions} of the {Equation} $n-\varphi(n)=c$},
     journal = {Matemati\v{c}eskie zametki},
     pages = {608--615},
     publisher = {mathdoc},
     volume = {109},
     number = {4},
     year = {2021},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2021_109_4_a11/}
}