Enid Blyton. (2018). The Secret Seven, Mystery of the Skull (2018.). Hodder Children's book.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रEnid Blyton. The Secret Seven, Mystery of the Skull. 2018. Hodder Children's book, 2018.
एमएलए (9वां संस्करण) प्रशस्ति पत्रEnid Blyton. The Secret Seven, Mystery of the Skull. 2018. Hodder Children's book, 2018.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.