Pfeiffer, W. S., & Keller, C. H. (2000). Proposal writing: The art of friendly and winning persuasion. Prentice Hall.
Lua i Stíl Chicago (17ú heag.)Pfeiffer, William S., agus Charles H. Keller. Proposal Writing: The Art of Friendly and Winning Persuasion. Upper Saddle River, NJ: Prentice Hall, 2000.
Lua MLA (9ú heag.)Pfeiffer, William S., agus Charles H. Keller. Proposal Writing: The Art of Friendly and Winning Persuasion. Prentice Hall, 2000.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.