BLY ROBERT W. (1992). BUSINESS TO BUSINESS DIRECT MARKETING. NTC BUSINESS BOOKS.
Lua i Stíl Chicago (17ú heag.)BLY ROBERT W. BUSINESS TO BUSINESS DIRECT MARKETING. LINCOLNWOOD: NTC BUSINESS BOOKS, 1992.
Lua MLA (9ú heag.)BLY ROBERT W. BUSINESS TO BUSINESS DIRECT MARKETING. NTC BUSINESS BOOKS, 1992.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.