Schools Council, Nuffield Foundation, Nuffield Foundation, & Scottish Education Department. (1973). Holes, gaps and cavities ; stages 1 & 2: A unit for teachers. MacDonald Educational.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Schools Council, Nuffield Foundation, Nuffield Foundation, و Scottish Education Department. Holes, Gaps and Cavities ; Stages 1 & 2: A Unit for Teachers. London: MacDonald Educational, 1973.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Schools Council, Nuffield Foundation, et al. Holes, Gaps and Cavities ; Stages 1 & 2: A Unit for Teachers. MacDonald Educational, 1973.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.