. . "Major labor-law principles established by the NLRB and the courts (December 1964 - April 1970)" . . . . "Digests" . . . "Major labor-law principles established by the NLRB and the courts : (December 1964-December 1973)"@en . "Digests"@en . "Major labor-law principles, established by the NLRB and the courts (December 1964 - December 1973)"@en . . "Major labor-law principles, established by the NLRB and the courts, December 1964- April 1970"@en . . . . "Major labor-law principles established by the NLRB and the courts, (December 1964 - April 1970)" . . . . . . "Major labor-law principles, established by the NLRB and the courts, December 1964-"@en . "Major labor-law principles, established by the NLRB and the courts (December 1964-December 1973)"@en . . . . . . . .