@article{10_4153_CJM_2009_008_2,
     author = {Laurent, Michel},
     title = {Exponents of {Diophantine} {Approximation} in {Dimension} {Two}},
     journal = {Canadian journal of mathematics},
     pages = {165--189},
     year = {2009},
     volume = {61},
     number = {1},
     doi = {10.4153/CJM-2009-008-2},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-2009-008-2/}
}