... medium¹

 Crystalline graphite has a strong resonant feature near $\lambda$ 11.52${\mu}\rm{m}$ (Draine, [1984]) which is not observed.

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... width²

 Note that the observed weakness of the bump strength in dense clouds can be attributed to the hydrogenation of carbon (Sorrell, [1990]).

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... Gold-type³

 Its idea was first suggested by Gold ([1952]).

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...fpell)⁴

 A similar conclusion follows from calculations made by Matsumura and Seki ([1996]).

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... ``correct''⁵

 ``Correctness'' is contained in the use of the measured optical constants for which real and imaginary parts are already connected by Kramers-Kronig relations but not a wavelength-independent refractive index.

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