[Establishing methods for assessing the degree of difficulty of exercises in mathematics for younger schoolchildren].

@article{Agarkov1981EstablishingMF,
  title={[Establishing methods for assessing the degree of difficulty of exercises in mathematics for younger schoolchildren].},
  author={V I Agarkov},
  journal={Gigiena i sanitariia},
  year={1981},
  volume={10},
  pages={64-6}
}