It's kinda' nice when we go to sell and we can say "pictured on page so and so in so and so's book". More importantly though is really to support fellow collectors who invest exrutiating time and put forth massive effort to put a reference book together. I doubt Mike is making much $$ on the book (if at all) and I think in his case it was more of something he's wanted to do for quite awhile. I have doubts it'll reach sales levels that parity the Harry Potter books
. It should fill a nice void however. There's not too terribly much reference out there on Japanese imperial booty.
Good collecting my friends,
Tom
