PORTNOY ROBERT A. (1986). LEADERSHIP: WHAT EVERY LEADER SHOULD KNOW ABOUT PEOPLE. PRENTICE -HALL INTERNATIONAL, INC.
Lua i Stíl Chicago (17ú heag.)PORTNOY ROBERT A. LEADERSHIP: WHAT EVERY LEADER SHOULD KNOW ABOUT PEOPLE. NEW JERSEY: PRENTICE -HALL INTERNATIONAL, INC, 1986.
Lua MLA (9ú heag.)PORTNOY ROBERT A. LEADERSHIP: WHAT EVERY LEADER SHOULD KNOW ABOUT PEOPLE. PRENTICE -HALL INTERNATIONAL, INC, 1986.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.