@incollection{MEM_2021_50_a33,
     author = {Pashev, George and Doneva, Rositsa and Gaftandzhieva, Silvia},
     title = {An application of accumulative frame models in programming training},
     booktitle = {},
     series = {Mathematics and Education in Mathematics},
     pages = {284--289},
     year = {2021},
     volume = {50},
     language = {bg},
     url = {http://geodesic.mathdoc.fr/item/MEM_2021_50_a33/}
}