Huggins, W. Further observations on the spectra of some of the stars and nebulae, with an attempt to determine therefrom whether these bodies are moving towards or from the Earth, also observations on the spectra of the Sun and of Comet II // Philosophical Transactions of the Royal Society of London 158 (0). 1868. DOI:10.1098/rstl.1868.0022. с. 529 – 564.
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Henry Draper Medal // National Academy of Sciences. Посетен на 19 февруари 2011.