Cita APA

Hellman, J. A. 1. (2003). The riddle of distance education: Promise, problems and applications for development. Geneva, Switzerland: United Nations Research Institute for Social Development.

Citación estilo Chicago

Hellman, Judith Adler 1945-. The Riddle of Distance Education: Promise, Problems and Applications for Development. Geneva, Switzerland: United Nations Research Institute for Social Development, 2003.

Cita MLA

Hellman, Judith Adler 1945-. The Riddle of Distance Education: Promise, Problems and Applications for Development. Geneva, Switzerland: United Nations Research Institute for Social Development, 2003.