@article{MO_2015_75_3_a4,
     author = {T. Ehrenfest-Afanassjewa},
     title = {Exercises in experimental geometry},
     journal = {Matemati\v{c}eskoe obrazovanie},
     pages = {39--46},
     publisher = {mathdoc},
     volume = {75},
     number = {3},
     year = {2015},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MO_2015_75_3_a4/}
}