It's not expensive but I have a copy and it was not worth it. The few photos of original pieces are from the Royal Armouries Leeds and are printed tiny.
As far as the 'Medieval' site is concerned: how serious can you expect a booklet to be when the title (!) page illustrates a true Medieval long gun next to a detached wall gun barrel of ca. 1
600 when the Middle Ages were over for 100 years?!
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