Marco's Comments:
The rare book by Robert Harbin. It is always more difficult to find a copy and these sell for huge amount of money. This is the original book... copies of it are sold as well (they are bound photocopies) and a "pirate" edition, which doesn't have Harbin's signature and a shiny cover (apparently, this was printed by Al Mann). Mine is the original book: on page 154 there is a small sticker with an extra paragraph (beginning with "This is confusing..."), clarifying the explanation of "The Invisible Man".