Harper, J. R. (1915). A survey of opportunities for vocational education in and near Philadelphia. Public Education Association.
Chicago-referens (17:e uppl.)Harper, Jane Roberts. A Survey of Opportunities for Vocational Education in and Near Philadelphia. Philadelphia: Public Education Association, 1915.
MLA-referens (8:e uppl.)Harper, Jane Roberts. A Survey of Opportunities for Vocational Education in and Near Philadelphia. Public Education Association, 1915.
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