(from Amazon Japan):

All six variations of Doraemon's first meeting with Nobita in one collection!

In commemoration of Doraemon's 50th anniversary, all 6 original versions of the first "Doraemon" chapter are compiled in their entirety. Also included is the legendary preview, where the title and main characters weren't decided until just minutes before the manga's deadline, and a secret "The Birth of Doraemon" chapter written by the creator himself! The entire collection is in the brand-new Shinsho book format, and the commentary at the end is full of rare photos as well as materials!