Bell, A. W. (1976). The learning of general mathematical strategies ; a developmental study of process attainments in mathematics, including the construction and investigation of a process-oriented curriculum for the first secondary year.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Bell, A. W. The Learning of General Mathematical Strategies ; a Developmental Study of Process Attainments in Mathematics, Including the Construction and Investigation of a Process-oriented Curriculum for the First Secondary Year. Nottingham, 1976.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Bell, A. W. The Learning of General Mathematical Strategies ; a Developmental Study of Process Attainments in Mathematics, Including the Construction and Investigation of a Process-oriented Curriculum for the First Secondary Year. 1976.