Macbeth, D. R. (1971). The extent to which pupils manipulate materials and attainment of process skills in elementary school science.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Macbeth, Douglas Russell. The Extent to Which Pupils Manipulate Materials and Attainment of Process Skills in Elementary School Science. 1971.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Macbeth, Douglas Russell. The Extent to Which Pupils Manipulate Materials and Attainment of Process Skills in Elementary School Science. 1971.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.