@incollection{MEM_2021_50_a43,
     author = {Petkov, Pavlin and Georgieva, Sevdalina and Koleva, Elena},
     title = {Mathematics in an electronic environment with {Geogebra} {Activity}  {(M૯GA)}},
     booktitle = {},
     series = {Mathematics and Education in Mathematics},
     pages = {373--380},
     year = {2021},
     volume = {50},
     language = {bg},
     url = {http://geodesic.mathdoc.fr/item/MEM_2021_50_a43/}
}