المؤلفون: Barker, F. Keith (Frederick Keith)
الوصول الحر: https://www.europeana.eu/item/08711/https___www_biodiversitylibrary_org_item_262885?utm_source=api&utm_medium=api&utm_campaign=YuvuWBeCaTest
المؤلفون: Barker, F. Keith (Frederick Keith), LeCroy, Mary.
الوصول الحر: https://www.europeana.eu/item/08711/https___www_biodiversitylibrary_org_item_280891?utm_source=api&utm_medium=api&utm_campaign=YuvuWBeCaTest