Date of book / How can I tell a first edition.

[enfable]

I've got a book, The Magic Faraway Tree, which states in it; First Published 1943.

There is not another date in the book and I know that it was first published in that year.

The dust cover appears to be the same as the first edition books but I do not know if this would have changed when other early editions were printed. I know there was a edition in 1946 but have no idea what the dust cover was like or if it had a date in it.

In short how can I tell if it is a first edition?

[Rollo]

This may assist:

http://www.millersmiles.co.uk/bookguide/firste ditionbooks/firsteditionbooks.htm

[enfable]

Thanks Rollo, just what I was after