General Certificate of Secondary Education & Suffolk County Council. (1987). Co-ordinated science lesson notes: Biology. Collins Educational.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)General Certificate of Secondary Education و Suffolk County Council. Co-ordinated Science Lesson Notes: Biology. London: Collins Educational, 1987.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)General Certificate of Secondary Education و Suffolk County Council. Co-ordinated Science Lesson Notes: Biology. Collins Educational, 1987.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.