> a <- "Wrocław"
> a
[1] "Wroclaw"

> Sys.getlocale()
[1] "LC_COLLATE=English_United States.1252;LC_CTYPE=English_United States.1252;LC_MONETARY=English_United States.1252;LC_NUMERIC=C;LC_TIME=English_United States.1252"

Sys.setlocale("LC_ALL", "Polish")

> a <- "Wrocław"
> a
[1] "Wroc³aw"