United States. National Science Foundation. Division of Intergovernmental Science & Public Technology & Boucher, W. I. (1977). The study of the future: An agenda for research. National Science Foundation, Research Applications Directorate, RANN-Research Applied to National Needs, Division of Intergovernmental Science and Public Technology : for sale by the Supt. of Docs., U. S. Govt. Print. Off..
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)United States. National Science Foundation. Division of Intergovernmental Science & Public Technology و Wayne I. Boucher. The Study of the Future: An Agenda for Research. Washington: National Science Foundation, Research Applications Directorate, RANN-Research Applied to National Needs, Division of Intergovernmental Science and Public Technology : for sale by the Supt. of Docs., U. S. Govt. Print. Off., 1977.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)United States. National Science Foundation. Division of Intergovernmental Science & Public Technology و Wayne I. Boucher. The Study of the Future: An Agenda for Research. National Science Foundation, Research Applications Directorate, RANN-Research Applied to National Needs, Division of Intergovernmental Science and Public Technology : for sale by the Supt. of Docs., U. S. Govt. Print. Off., 1977.