Jelaskan Deleng uga dari Alexander Graham Bell dalam bahasa banyumasan

Bell Homestead, National Historic Site

Alexander Bell.com - Telecom Pionneers by Phonebook of the World.com

Pidato Bell di hadapan American Association for the Advancement of Science di Boston pada 27 Agustus 1880, menghadirkan fotopon. Dimuat sebagai "On the Production and Reproduction of Sound by Light" di American Journal of Sciences, Third Series, vol. XX, #118, Oktober 1880, hh. 305 - 324; dan sebagai "Selenium and the Photophone" di Nature, September 1880