Back
“Snapshot.” Accessed December 19, 2016. https://books.google.fr/books?hl=en&lr=&id=R3XfBQAAQBAJ&oi=fnd&pg=PA227&dq=info:E2-fuFjuDzYJ:scholar.google.com&ots=TGHtxxyI4M&sig=Bn6AIsNE4ldQhnZq_eGVBTngrlg&redir_esc=y#v=onepage&q&f=false.