C. Heber D. (Feb 1911). «Methods of Silvering Mirrors». Publications of the Astronomical Society of the Pacific23 (135): 15–19. doi:10.1086/122040. Bibcode: 1911PASP...23...13C.
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C. Heber D. (Feb 1911). «Methods of Silvering Mirrors». Publications of the Astronomical Society of the Pacific23 (135): 15–19. doi:10.1086/122040. Bibcode: 1911PASP...23...13C.