Ostwald, Wilhelm; Taylor, W.W., trans. (1912). Outlines of General Chemistry (3rd изд.). London, England: Macmillan and Co., Ltd. стр. 104. From p. 104: "Substances are known which exist not only in two, but even in three, four or five different solid forms; no limitation to the number is known to exist. Such substances are called polymorphous. The name allotropy is commonly employed in the same connexion, especially when the substance is an element. There is no real reason for making this distinction, and it is preferable to allow the second less common name to die out."
Mary Anne White; et al. (24. 9. 2020). „The Relative Thermodynamic Stability of Diamond and Graphite”. Angewandte Chemie. 60 (3): 1546—1549. PMID32970365. S2CID221888151. doi:10.1002/anie.202009897.CS1 одржавање: Формат датума (веза)
Mary Anne White; et al. (24. 9. 2020). „The Relative Thermodynamic Stability of Diamond and Graphite”. Angewandte Chemie. 60 (3): 1546—1549. PMID32970365. S2CID221888151. doi:10.1002/anie.202009897.CS1 одржавање: Формат датума (веза)
Mary Anne White; et al. (24. 9. 2020). „The Relative Thermodynamic Stability of Diamond and Graphite”. Angewandte Chemie. 60 (3): 1546—1549. PMID32970365. S2CID221888151. doi:10.1002/anie.202009897.CS1 одржавање: Формат датума (веза)