Hayes, S. P. (1966). Evaluating development projects: A manual for the use of field workers (2nd ed., rev.). Unesco.
Cita Chicago (17th ed.)Hayes, Samuel Perkins. Evaluating Development Projects: A Manual for the Use of Field Workers. 2nd ed., rev. [Paris]: Unesco, 1966.
Cita MLA (9th ed.)Hayes, Samuel Perkins. Evaluating Development Projects: A Manual for the Use of Field Workers. 2nd ed., rev. Unesco, 1966.
Atenció: Aquestes cites poden no estar 100% correctes.