Deletion of Sidechain (ledger) (2nd nomination)

Comment: to Blockchain#Types. The previous AfD noted some reliable sources: A page or two in the book https://books.google.com/books?id=_HatDwAAQBAJ&newbks=1&newbks_redir=0&lpg=PP1&dq=sidechain%20ledger&pg=PP1#v=onepage&q=sidechain&f=false published by CRC Press and a solid page in the book https://books.google.com/books?id=LchFDAAAQBAJ&lpg=PA261&vq=sidechain&dq=sidechain&pg=PA261#v=snippet&q=sidechain&f=false published by Princeton University Press. There is a briefer mention in the book https://books.google.com/books?id=fvywDAAAQBAJ&pg=PA22&hl=en#v=onepage&q=sidechain&f=false published by O'Reilly. All three are good sources. They might be enough for marginal notability, but are definitely enough for verifiability of basic facts about sidechain technology. According to our policy , we prefer alternatives to deletion for verifiable material. In this case, sidechains are a special type of blockchain, so the blockchain article would be a good target for a merge. --&#123;&#123;u&#124
Stance: merge
Cited policy: Wikipedia:Deletion policy (WP:ATD)