“…In a small number of cases the diagnosis was made by lung biopsy (Rubin, 1955;Ellman, 1956;Flatley, 1959;Hortler and Thompson, 1959;Ognibene, 1960;Robertson and Brinkman, 1961). More often the diagnosis has been only clinical (Ellman and Ball, 1948;Hart, 1948;Schlesinger, 1949 ;Ellman and Weber, 1949;Leys and Swift, 1949;Bloom and Rubin, 1950;Middleton. 19)51 ;Stolte, 1952;Harris, 1954;Rubin, 1955;Spence, 1955;Ellman, 1956;Horler and Thompson, 1959).…”