@article{DAN_1977_235_3_a11,
     author = {N. A. Shirokov},
     title = {Approximate entropy of continua},
     journal = {Doklady Akademii Nauk},
     pages = {546--549},
     publisher = {mathdoc},
     volume = {235},
     number = {3},
     year = {1977},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1977_235_3_a11/}
}