51 pounds is too much. Try to find it at maximum 30-40 USD, search the web or ask in the bookstores, somewhere should be. I wouldn't call it invaluable, when you have an ASDL connection. It is a useful quick reference at hand for "triangle" translations, in my case from IT through ENG into RU, and vice versa. It does spare time of surfing the net, yet I prefer surfing and always manage to find necessary parallel texts and illustrations. Now we have such big resources as multilingual Wikipedia and others. The last time I looked through my IT-ENG Duden was a few months ago.
I think there are no downloadable versions of Pictorial Dudens.
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