SUMANTH DAVID J. (1985). PRODUCTIVITY ENGINEERING & MANAGEMENT. MCGRAW-HILL.
Lua i Stíl Chicago (17ú heag.)SUMANTH DAVID J. PRODUCTIVITY ENGINEERING & MANAGEMENT. NEW YORK: MCGRAW-HILL, 1985.
Lua MLA (9ú heag.)SUMANTH DAVID J. PRODUCTIVITY ENGINEERING & MANAGEMENT. MCGRAW-HILL, 1985.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.