My books are originally written in Dutch (although I’m not Dutch! I’m Belgian. In the northern part of Belgium we speak Dutch, the same language as in the Netherlands, but with slightly different words and a different accent. Much like the difference between American English and British English, or German German and Austrian German.)
A lot of my books have been translated in several languages such as English, German, French, Spanish, Arabic, Danish, Korean, … So pick any version you can read :-)