Peter Freeland. (1991). Focus on biology: Habitats and the environment,investigation. London: Hodder and Stoughton.
استشهاد بنمط شيكاغوPeter Freeland. Focus On Biology: Habitats and the Environment,investigation. London: Hodder and Stoughton, 1991.
MLA استشهادPeter Freeland. Focus On Biology: Habitats and the Environment,investigation. London: Hodder and Stoughton, 1991.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.