Campo elettromagnetico: differenze tra le versioni

|isbn=3-11-015777-2

|capitolo=4.5.1

|url=http://books.google.com/books?id=8vAC8YG41goC}}, [http://books.google.com/books?id=8vAC8YG41goC&pg=PA360 Extract of pages 360-361]

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