Yrsa Sigurðardóttir. (2013). The day is dark (1st U.S. ed.). Minotaur Books/Thomas Dunne Books.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रYrsa Sigurðardóttir. The Day Is Dark. 1st U.S. ed. New York: Minotaur Books/Thomas Dunne Books, 2013.
एमएलए (8वां संस्करण) प्रशस्ति पत्रYrsa Sigurðardóttir. The Day Is Dark. 1st U.S. ed. Minotaur Books/Thomas Dunne Books, 2013.
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