Toole, G., & Toole, S. (1999). Understanding biology for advanced level (4th ed.). Cheltenham: Stanley Thornes Publishers.
Παραπομπή Chicago StyleToole, Glenn, and Susan Toole. Understanding Biology for Advanced Level. 4th ed. Cheltenham: Stanley Thornes Publishers, 1999.
Παραπομπή MLAToole, Glenn, and Susan Toole. Understanding Biology for Advanced Level. 4th ed. Cheltenham: Stanley Thornes Publishers, 1999.
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