AFT LAWRENCE S. (1985). PRODUCTIVITY MEASUREMANT & IMPROVEMENT. RESTON PUBLISHERS.
Lua i Stíl Chicago (17ú heag.)AFT LAWRENCE S. PRODUCTIVITY MEASUREMANT & IMPROVEMENT. VIRGINIA: RESTON PUBLISHERS, 1985.
Lua MLA (9ú heag.)AFT LAWRENCE S. PRODUCTIVITY MEASUREMANT & IMPROVEMENT. RESTON PUBLISHERS, 1985.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.