@article{MZM_1999_66_4_a0,
     author = {Yu. M. Alexencev},
     title = {On the measure of approximation of $\pi$ by algebraic numbers},
     journal = {Matemati\v{c}eskie zametki},
     pages = {483--493},
     publisher = {mathdoc},
     volume = {66},
     number = {4},
     year = {1999},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1999_66_4_a0/}
}