@article {MR2274902,
	title = {Comments on the spectra of Pisot numbers},
	journal = {J. Number Theory},
	volume = {121},
	year = {2006},
	pages = {187{\textendash}203},
	issn = {0022-314X},
	doi = {10.1016/j.jnt.2006.02.003},
	url = {http://dx.doi.org/10.1016/j.jnt.2006.02.003},
	author = {Garth, David and Hare, Kevin G.}
}
