One of the sources of this book is my own site; StarWarsInterviews.com, on which more than 170 interviews with the cast and crew of Star Wars.
I am therefore very proud of the mail I received from WR Miller, the author of this book, earlier today: The Star Wars Historical Sourcebook Volume 1: 1971-1976 will appear on 17 July 2018 and be on sale at Amazon.com (price nnb).
No less than Gary Kurtz (producer of Star Wars and The Empire Strikes Back) has written the foreword in which he has to say this:
"Bob Miller has done a monumental job on this sourcebook and any true
Star Wars fan or scholar must have this work in their collection. "
More information about this book (which contains the 400 pages) is on Miller's site to read and of course there will be a review here!