The author's other titles aren't particularly sought-after.

The various other bits of documentation definitely make your copy more interesting than the average.

With one in the Brit. Lib. and your copy I'd imagine that makes three known copies - a publisher like Allen Unwin will have at least one file copy.

I have a few titles that, as far as I can find out, are either unique or one of only a pair known. That doesn't mean they have any great value, though.

. ------------------------------------------------------------------------------------------------------------------------------------------------------Whomever you may murder, there's no police like Holmes.
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