%0 Journal Article %T Assessment of the Level of Abstractness of Material Statement of in Natural Sciences School Textbooks %A Mayer, R.V. %K didactics, qualimetry, mathematical methods, method of pair comparisons, pedagogy, pedagogical expertise, complexity, learning theory. %J Standards and Monitoring in Education %D 2017 %N 5 %P 5 %I INFRA-M Academic Publishing LLC.