@article {MR1997583,
	title = {Non-trivial quadratic approximations to zero of a family of cubic Pisot numbers},
	journal = {Trans. Amer. Math. Soc.},
	volume = {355},
	year = {2003},
	pages = {4767{\textendash}4779},
	issn = {0002-9947},
	doi = {10.1090/S0002-9947-03-03333-6},
	url = {http://dx.doi.org/10.1090/S0002-9947-03-03333-6},
	author = {Borwein, Peter and Hare, Kevin G.}
}
