@article{MEM_2010_39_1_a27,
     author = {{\CYRB}{\cyra}{\cyre}{\cyrv}{\cyra}, {\CYRS}{\cyri}{\cyrl}{\cyrv}{\cyri}{\cyrya}},
     title = {{\CYRO}{\cyrp}{\cyrt}{\cyri}{\cyrm}{\cyri}{\cyrz}{\cyra}{\cyrc}{\cyri}{\cyrya} {\cyrn}{\cyra} {\cyru}{\cyrch}{\cyri}{\cyrt}{\cyre}{\cyrl}{\cyrs}{\cyrk}{\cyri}{\cyrya} {\cyrs}{\cyrhrdsn}{\cyrs}{\cyrt}{\cyra}{\cyrv} {\cyrv} {\cyru}{\cyrch}{\cyri}{\cyrl}{\cyri}{\cyrshch}{\cyre}},
     journal = {Mathematics and Education in Mathematics},
     pages = {250--256},
     publisher = {mathdoc},
     volume = {39},
     number = {1},
     year = {2010},
     language = {bg},
     url = {http://geodesic.mathdoc.fr/item/MEM_2010_39_1_a27/}
}