Analysis of information sources in references of the Wikipedia article "Photograph" in English language version.
from Helmut Gernsheim's article, "The 150th Anniversary of Photography," in History of Photography Vol. I, No. 1, January 1977: ... In 1822, Niépce coated a glass plate ... The sunlight passing through ... This first permanent example ... was destroyed ... some years later.
from Helmut Gernsheim's article, "The 150th Anniversary of Photography," in History of Photography Vol. I, No. 1, January 1977: ... In 1822, Niépce coated a glass plate ... The sunlight passing through ... This first permanent example ... was destroyed ... some years later.