In English you can find them from the publisher in Canada (Fedorowicz) or from the Abderdeen Bookstore in the USA. Tom at Aberdeen has the whole series, all five, for anyyone looking for them. I think Fedorowicz might offer a deal if you buy all five at once.
Then there's the usual alternate sites, such as abebooks and Amazon sellers. Amazon.de might be the best place to find the German editions.
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