You should contact them, authors usually have a way to do that (email, private message, etc.)
ifius a dit
Probablemente no es una fuente
You might want to take a look at this font, it's the first one that comes to my mind: http://www.dafont.com/linkinpark-chase.font
But if you really like a font, and you just need an R like this, I'd say it's easier for you to just modify it in Illustrator rather than spend hours looking for something you might not find.
It would probably be easier for you to just modify one letter (in Illustrator for example) especially if it's just for a title (but I'm assuming you need this only for a title).
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