double and Xu Xi's "The stone window"

Xu Xi one of few Hong kong authors who write in English
Daughters of Hui

literature on double:
Fred Botting. 1996 The Gothic. Routledge

Otto Rank 1971 Beyond psychology(1941). New York: Dover.

Andrew Webber. 1996. The Doppelganger: Double visions in German Literature. Oxford University Press