1. R. Minc, O topologičeskoĭ ekvivalentnosti sostoyaniĭ ravnovesiya sistemy treh differencial’ nyh uravneniĭ, Nauč. Dokl. Vysš. Školy, Fiz.-Mat. Nauki (1958), no. 1, 19-24.
2. Topological classification of neighborhoods of a singularity in 𝑛-space;Grobman, D. M.;Mat. Sb. (N.S.),1962
3. On local homeomorphisms of Euclidean spaces;Hartman, Philip;Bol. Soc. Mat. Mexicana (2),1960
4. Contributions to stability theory;Massera, José L.;Ann. of Math. (2),1956