Singer, H. W. (1977). Technologies for basic needs. International Labor Office.
Cita Chicago (17th ed.)Singer, Hans Wolfgang. Technologies for Basic Needs. Geneva: International Labor Office, 1977.
Cita MLA (9th ed.)Singer, Hans Wolfgang. Technologies for Basic Needs. International Labor Office, 1977.
Atenció: Aquestes cites poden no estar 100% correctes.