it is. though not too
hard to find.
i recently bought it on ebay for only 5,- EUR. a bargain.
i'd say it sure is worth 15,- to 20,- EUR. it was the only Buk-publication in the GDR.
i see, there's someone selling it for 6,35 EUR
(strange price, eh?) now. i'd definitely go for it at that price.