Harper, J. R. (1915). A survey of opportunities for vocational education in and near Philadelphia. Public Education Association.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Harper, Jane Roberts. A Survey of Opportunities for Vocational Education in and Near Philadelphia. Philadelphia: Public Education Association, 1915.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Harper, Jane Roberts. A Survey of Opportunities for Vocational Education in and Near Philadelphia. Public Education Association, 1915.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.