Ople, B. F. Proposals for further development: Manpower planning ; vocational and career guidance. s.n.].
芝加哥风格引文Ople, Blas F. Proposals for Further Development: Manpower Planning ; Vocational and Career Guidance. [S.l: s.n.].
MLA引文Ople, Blas F. Proposals for Further Development: Manpower Planning ; Vocational and Career Guidance. s.n.].
警告：这些引文格式不一定是100％准确.