APA

National Federation of Building Trades Employers, . (1950). Sub-contract...issued under the sanction of and approved by the National Federation of Building Trades Employers and the Federation of Associations of Specialists and Sub-contractors. London: National Federation of Building Trades E.

Chicago

National Federation of Building Trades Employers, . 1950. Sub-contract...issued under the sanction of and approved by the National Federation of Building Trades Employers and the Federation of Associations of Specialists and Sub-contractors. London: National Federation of Building Trades E.

Harvard

National Federation of Building Trades Employers, . (1950). Sub-contract...issued under the sanction of and approved by the National Federation of Building Trades Employers and the Federation of Associations of Specialists and Sub-contractors. London: National Federation of Building Trades E.

MLA

National Federation of Building Trades Employers, . Sub-contract...issued under the sanction of and approved by the National Federation of Building Trades Employers and the Federation of Associations of Specialists and Sub-contractors. London: National Federation of Building Trades E. 1950.