SCOTT DRU. (1991). CUSTOMER SATISFACTION: THE OTHER HALF OF YOUR JOB. CRISP PUBLICATION.
Lua i Stíl Chicago (17ú heag.)SCOTT DRU. CUSTOMER SATISFACTION: THE OTHER HALF OF YOUR JOB. CALIFORNIA: CRISP PUBLICATION, 1991.
Lua MLA (9ú heag.)SCOTT DRU. CUSTOMER SATISFACTION: THE OTHER HALF OF YOUR JOB. CRISP PUBLICATION, 1991.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.