Sleep's mythical domain (4,2,3)

I believe the answer is:

land of nod

(Other definitions for land of nod that I've seen before include "east of 27 [EDEN]" , "Where Cain went after slaying Abel" , "Dropping-off place" , "dropping-off area?" , "Imaginary place of sleep" .)

I've seen this clue in the Sydney Morning Herald.

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