Note: In 1962 Smith had completed a Novel called "Subspace Safari", a sequel to the novelette "Subspace Survivors". Campbell wanted extensive changes which Smith refused to do, and Smith started rewriting it without the parts taken from the novelette. Eventually he decided it was too big for one book, so the first part came out as "Subspace Explorers" in 1965. He took time out to write Skylark Duquesne for Fred Pohl, and died before he could finish Subspace. Lloyd Arthur Eshbach had been a sounding-board for the second part as it was written though, and when some of this manuscript reappeared in 1978 (having gone from Eshbach to Pohl to David Kyle) Eshbach decided to attempt to complete it. The one-book manuscript and the rewrites sent to Eshbach enabled "Subspace Encounter" to be completed.