SCHAFFER ROBERT. (1986). MARKETING TOOLKIT: COMPUTER APPLICATIONS FOR MARKETING PRINCIPLES. ADDISON-WESLEY.
Lua i Stíl Chicago (17ú heag.)SCHAFFER ROBERT. MARKETING TOOLKIT: COMPUTER APPLICATIONS FOR MARKETING PRINCIPLES. MASSACHUSETTS: ADDISON-WESLEY, 1986.
Lua MLA (9ú heag.)SCHAFFER ROBERT. MARKETING TOOLKIT: COMPUTER APPLICATIONS FOR MARKETING PRINCIPLES. ADDISON-WESLEY, 1986.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.