Butler, Reginald ChristopherReginald ChristopherButlerPiro, L.L.Piro2020-09-172020-09-171995-01-01https://hdl.handle.net/20.500.13025/4258High Energy Astrophysicsbookhttp://books.google.it/books?id=zITvAAAAMAAJ&pgis=1&redir_esc=y54ea4c3f61d11ff0358a875a