Allen, L. A. (1975). Professional management: New concepts and proven practices. Tata McGraw-Hill.
Dyfyniad Arddull ChicagoAllen, Louis A. Professional Management: New Concepts and Proven Practices. Tata McGraw-Hill, 1975.
Dyfyniad MLAAllen, Louis A. Professional Management: New Concepts and Proven Practices. Tata McGraw-Hill, 1975.
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