non-ASCII characters are not displayed correctly

[FvD]

Author names with special characters such as é, ñ etc are not displayed correctly. Either the special character is removed or alternative characters are inserted.

Some examples:

Manuel López-Ibáñez instead of Manuel López-Ibáñez Héctor Villalobos instead of Héctor Villalobos Gergely Daróczi instead of Gergely Daróczi Frans van Dunn instead of Frans van Dunné

On the CRAN pages the characters are shown correctly in all these cases.